8/16/2019

1

BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________,

__________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = _________________________________________________________________________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their

evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long

period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

– Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example, growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the

experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only

since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the

independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the

results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage

may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below

the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified

report

– Cannot be generalized to the larger population because it isn’t based on empirical

evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that

attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other

tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little

compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical

copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and

behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and

mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in

size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae, Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists

of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major

organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

– Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

– How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those

instructions are carried to the ribosomes out in the cytoplasm on a molecule

called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic

reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and

estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more

of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out

organelles

– Peroxisomes take up ___________________ and degrade them into harmless

waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the

products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and

fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine

________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with

numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a

tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around

the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the

cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its

flexibility

– Various types of _____________ may act as doors or gates, regulating what goes

into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute

concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid

bilayer easily

– ____________ or ______________________________ molecules can’t cross the

lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into

cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle

cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in

___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus,

nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for

example, if the groundwater is polluted with barium that may leak from

electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles

would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other

molecules

– This transfer of a phosphate group to another molecule is what causes cells to do

work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine

____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the

ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon

compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are

produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the

electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their

energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by

breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

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8/16/2019

2

BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________,

__________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = ________________________________________________________________

_________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their

evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long

period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

– Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example,

growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only

since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most

appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the

independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the

results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below

the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified

report

– Cannot be generalized to the larger population because it isn’t based on empirical evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that

attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other

tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little

compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical

copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and

behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and

mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in

size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae,

Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists

of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major

organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

– Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

– How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those

instructions are carried to the ribosomes out in the cytoplasm on a molecule

called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic

reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and

estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more

of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out

organelles

– Peroxisomes take up ___________________ and degrade them into harmless

waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the

products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and

fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine

________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with

numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a

tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around

the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the

cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its

flexibility

– Various types of _____________ may act as doors or gates, regulating what goes

into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute

concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid

bilayer easily

– ____________ or ______________________________ molecules can’t cross the

lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into

cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle

cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in

___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration

of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus,

nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for

example, if the groundwater is polluted with barium that may leak from

electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles

would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into

energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other

molecules

– This transfer of a phosphate group to another molecule is what causes cells to do work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine

____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the

ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon

compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are

produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the

electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their

energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic

food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by

breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

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8/16/2019

3

BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________, __________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = ________________________________________________________________

_________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their

evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long

period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

– Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example,

growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the

experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only

since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most

appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the

independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the

results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage

may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below

the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified

report

– Cannot be generalized to the larger population because it isn’t based on empirical

evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that

attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other

tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little

compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical

copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and

behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and

mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in

size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae,

Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists

of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major

organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

– Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

– How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those

instructions are carried to the ribosomes out in the cytoplasm on a molecule

called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic

reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and

estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more

of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out

organelles

– Peroxisomes take up ___________________ and degrade them into harmless

waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the

products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and

fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine

________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with

numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a

tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around

the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the

cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its

flexibility

– Various types of _____________ may act as doors or gates, regulating what goes

into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute

concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid

bilayer easily

– ____________ or ______________________________ molecules can’t cross the

lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle

cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in

___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration

of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus, nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for

example, if the groundwater is polluted with barium that may leak from

electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles

would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into

energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other

molecules

– This transfer of a phosphate group to another molecule is what causes cells to do

work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine

____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the

ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon

compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are

produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the

electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their

energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic

food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by

breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

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BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________,

__________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = ________________________________________________________________

_________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their

evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long

period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

– Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example,

growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the

experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only

since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most

appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the

independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the

results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage

may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below

the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified

report

– Cannot be generalized to the larger population because it isn’t based on empirical

evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that

attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other

tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little

compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical

copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and

behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and

mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in

size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae,

Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists

of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

– Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

– How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those

instructions are carried to the ribosomes out in the cytoplasm on a molecule

called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and

estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more

of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out

organelles

– Peroxisomes take up ___________________ and degrade them into harmless

waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the

products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and

fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine

________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with

numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a

tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around

the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the

cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its

flexibility

– Various types of _____________ may act as doors or gates, regulating what goes

into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute

concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid

bilayer easily

– ____________ or ______________________________ molecules can’t cross the

lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into

cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in

___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration

of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus,

nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for

example, if the groundwater is polluted with barium that may leak from

electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles

would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into

energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other

molecules

– This transfer of a phosphate group to another molecule is what causes cells to do

work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine

____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the

ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon

compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are

produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the

electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their

energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic

food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by

breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

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BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________,

__________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = ________________________________________________________________

_________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their

evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long

period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

– Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example,

growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the

experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most

appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the

independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the

results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage

may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below

the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified

report

– Cannot be generalized to the larger population because it isn’t based on empirical

evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that

attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other

tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little

compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical

copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and

behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and

mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in

size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae,

Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists

of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major

organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

– Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

– How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those

instructions are carried to the ribosomes out in the cytoplasm on a molecule

called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic

reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and

estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more

of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out

organelles

– Peroxisomes take up ___________________ and degrade them into harmless

waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the

products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and

fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine

________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with

numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around

the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the

cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its

flexibility

– Various types of _____________ may act as doors or gates, regulating what goes into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute

concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid

bilayer easily

– ____________ or ______________________________ molecules can’t cross the

lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into

cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle

cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in

___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration

of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus,

nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for

example, if the groundwater is polluted with barium that may leak from electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles

would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into

energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other

molecules

– This transfer of a phosphate group to another molecule is what causes cells to do

work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine

____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the

ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are

produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the

electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their

energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic

food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by

breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

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8/16/2019

6

BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________,

__________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = ________________________________________________________________

_________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long

period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

– Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example,

growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the

experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only

since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most

appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the

independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage

may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below

the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified

report

– Cannot be generalized to the larger population because it isn’t based on empirical

evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that

attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little

compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical

copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and

mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in

size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae,

Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists

of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major

organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

– Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

– How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those

instructions are carried to the ribosomes out in the cytoplasm on a molecule

called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic

reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and

estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more

of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out

organelles

– Peroxisomes take up ___________________ and degrade them into harmless

waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the

products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and

fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine

________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with

numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a

tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around

the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the

cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its

flexibility

– Various types of _____________ may act as doors or gates, regulating what goes

into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute

concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid

bilayer easily

– ____________ or ______________________________ molecules can’t cross the

lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into

cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle

cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in

___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration

of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus,

nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for

example, if the groundwater is polluted with barium that may leak from

electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles

would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into

energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other

molecules

– This transfer of a phosphate group to another molecule is what causes cells to do

work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine

____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the

ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon

compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are

produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the

electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their

energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic

food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by

breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

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8/16/2019

7

BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________,

__________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = ________________________________________________________________

_________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their

evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long

period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

– Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example,

growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the

experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only

since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most

appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the

independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the

results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage

may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified

report

– Cannot be generalized to the larger population because it isn’t based on empirical

evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that

attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other

tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little

compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical

copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and

behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in

size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae,

Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists

of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major

organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

– Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

– How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those

instructions are carried to the ribosomes out in the cytoplasm on a molecule called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic

reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and

estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more

of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out

organelles

– Peroxisomes take up ___________________ and degrade them into harmless

waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the

products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and

fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine

________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with

numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a

tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around

the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the

cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its

flexibility

– Various types of _____________ may act as doors or gates, regulating what goes

into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid

bilayer easily

– ____________ or ______________________________ molecules can’t cross the

lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into

cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle

cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in ___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration

of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus,

nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for example, if the groundwater is polluted with barium that may leak from

electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles

would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into

energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other

molecules

– This transfer of a phosphate group to another molecule is what causes cells to do

work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine

____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the

ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon

compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are

produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the

electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their

energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic

food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

1

2

3

4

5

6

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8/16/2019

8

BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________,

__________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = _________________________________________________________________________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their

evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long

period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

– Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example,

growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the

experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only

since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most

appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the

independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the

results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage

may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below

the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified

report

– Cannot be generalized to the larger population because it isn’t based on empirical

evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that

attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other

tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little

compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical

copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and

behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and

mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in

size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae,

Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists

of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major

organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

– Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

–How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those

instructions are carried to the ribosomes out in the cytoplasm on a molecule

called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic

reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and

estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more

of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out

organelles

– Peroxisomes take up ___________________ and degrade them into harmless

waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and

fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine

________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with

numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a

tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around

the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the

cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its

flexibility

– Various types of _____________ may act as doors or gates, regulating what goes

into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute

concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid

bilayer easily

– ____________ or ______________________________ molecules can’t cross the

lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into

cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle

cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in

___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration

of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus,

nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for

example, if the groundwater is polluted with barium that may leak from

electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles

would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other

molecules

– This transfer of a phosphate group to another molecule is what causes cells to do

work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine

____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the

ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon

compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are

produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their

energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic

food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by

breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

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8/16/2019

9

BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________,

__________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = ________________________________________________________________

_________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their

evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long

period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

– Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example,

growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only

since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most

appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the

independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the

results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below

the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified

report

– Cannot be generalized to the larger population because it isn’t based on empirical evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that

attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other

tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical

copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and

behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and

mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in

size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae,

Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists

of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major

organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

– Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

– How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those

instructions are carried to the ribosomes out in the cytoplasm on a molecule

called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic

reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more

of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out

organelles

– Peroxisomes take up ___________________ and degrade them into harmless

waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the

products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and

fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine

________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with

numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a

tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the

cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its

flexibility

– Various types of _____________ may act as doors or gates, regulating what goes

into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute

concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid

bilayer easily

– ____________ or ______________________________ molecules can’t cross the

lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into

cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle

cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in

___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration

of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus,

nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for

example, if the groundwater is polluted with barium that may leak from

electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles

would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into

energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other

molecules

– This transfer of a phosphate group to another molecule is what causes cells to do work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine

____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the

ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon

compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are

produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the

electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their

energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic

food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by

breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

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8/16/2019

10

BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________,

__________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = ________________________________________________________________

_________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their

evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

– Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example,

growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the

experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only

since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most

appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the

independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the

results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage

may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below

the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified

report

– Cannot be generalized to the larger population because it isn’t based on empirical

evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that

attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other

tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little

compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and

behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and

mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae,

Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists

of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major

organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

–Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

– How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those

instructions are carried to the ribosomes out in the cytoplasm on a molecule

called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic

reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and

estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more

of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out

organelles

– Peroxisomes take up ___________________ and degrade them into harmless waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the

products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and

fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine

________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with

numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a

tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around

the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the

cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its

flexibility

– Various types of _____________ may act as doors or gates, regulating what goes

into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute

concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid

bilayer easily

– ____________ or ______________________________ molecules can’t cross the

lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle

cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in

___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration

of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus,

nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for

example, if the groundwater is polluted with barium that may leak from

electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles

would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into

energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other

molecules

– This transfer of a phosphate group to another molecule is what causes cells to do

work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine

____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the

ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon

compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are

produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the

electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their

energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic

food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by

breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

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BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________,

__________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = ________________________________________________________________

_________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their

evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long

period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

– Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example,

growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the

experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only

since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most

appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the

results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage

may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below

the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified report

– Cannot be generalized to the larger population because it isn’t based on empirical

evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that

attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other

tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little

compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical

copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and

behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and

mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in

size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae,

Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists

of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major

organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

– Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

– How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those

instructions are carried to the ribosomes out in the cytoplasm on a molecule

called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic

reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and

estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more

of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out

organelles

– Peroxisomes take up ___________________ and degrade them into harmless

waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the

products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and

fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine

________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with

numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a

tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around

the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its

flexibility

– Various types of _____________ may act as doors or gates, regulating what goes

into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute

concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid

bilayer easily

– ____________ or ______________________________ molecules can’t cross the

lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into

cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in

___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration

of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus,

nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for

example, if the groundwater is polluted with barium that may leak from

electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles

would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into

energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other molecules

– This transfer of a phosphate group to another molecule is what causes cells to do

work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine

____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the

ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon

compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are

produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the

electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their

energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic

food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by

breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

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BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________,

__________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = ________________________________________________________________

_________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their

evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long

period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

– Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example,

growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the

experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only

since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most

appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the

independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the

results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage

may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below

the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified

report

– Cannot be generalized to the larger population because it isn’t based on empirical

evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that

attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other

tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little

compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical

copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and

behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and

mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in

size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae,

Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major

organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

– Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

– How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those

instructions are carried to the ribosomes out in the cytoplasm on a molecule

called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic

reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and

estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out organelles

– Peroxisomes take up ___________________ and degrade them into harmless

waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the

products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine

________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a

tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around

the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the

cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its

flexibility

– Various types of _____________ may act as doors or gates, regulating what goes into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute

concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid

bilayer easily

– ____________ or ______________________________ molecules can’t cross the lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into

cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle

cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in

___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration

of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus,

nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for

example, if the groundwater is polluted with barium that may leak from electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles

would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into

energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other

molecules

– This transfer of a phosphate group to another molecule is what causes cells to do

work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine

____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the

electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their

energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic

food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by

breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

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8/16/2019

13

BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________,

__________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = ________________________________________________________________

_________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long

period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

–Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example,

growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the

experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only

since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most

appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the

independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the

results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage

may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below

the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified

report

– Cannot be generalized to the larger population because it isn’t based on empirical

evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little

compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical

copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and

behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and

mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in

size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae,

Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists

of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major

organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

– Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

– How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those

instructions are carried to the ribosomes out in the cytoplasm on a molecule

called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic

reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and

estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more

of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out

organelles

– Peroxisomes take up ___________________ and degrade them into harmless

waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the

products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and

fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine ________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with

numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a

tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around

the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the

cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its

flexibility

– Various types of _____________ may act as doors or gates, regulating what goes

into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute

concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid

bilayer easily

– ____________ or ______________________________ molecules can’t cross the

lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into

cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle

cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in

___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration

of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus,

nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for

example, if the groundwater is polluted with barium that may leak from

electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into

energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other

molecules

– This transfer of a phosphate group to another molecule is what causes cells to do

work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine

____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the

ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon

compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are

produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the

electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their

energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic

food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by

breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

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8/16/2019

14

BIO 1102 Lec. 2 (guided notes) Part A:Chapter 1 – Human Biology, Science & Society

Biology is the Study of Life

• What is life?

– Living things have a different ___________________ than nonliving things

• Certain elements are much more common in living things, such as

____________, ______________, _____________ and __________________ (96% of the mass of living things)

• Can make certain kinds of compounds (_________________,

__________________, ________________ and _____________)

– Living things require energy and raw materials

• They have a ________________ – physical and chemical processes that transform energy and molecules

–

•

•

– Living things are composed of cells

• Cell = ________________________________________________________________

_________________________

• May be unicellular or multicellular

– Living things maintain homeostasis

• __________________ = the maintenance of relatively constant physical and chemical internal environment

– Living things respond to their external environment

– Living things grow and reproduce

– Populations of living things evolve

–

Living Things are Grouped According to Their Characteristics

• Biologists use a hierarchical classification system to group organisms based on their

evolutionary relationships

• The main categories of this classification system are:

–Domain

– Kingdom

– Phylum

– Class

–Order

– Family

– Genus

– Species

• Humans are classified as:

–Domain Eukarya

– Kingdom _________________

– Phylum Chordata

– Class _____________

–Order _____________

– Family Hominidae

– Genus Homo

– Species _____________________

• What makes us human?

– _________________: we’re the only species of mammal that prefers to walk upright on two legs

– ________________________: humans, along with several other primate species, can move our thumbs in opposition to the tips of all of our other fingers

– ______________________: Our brains continue to grow for a relatively long

period after birth, giving us a large brain size; this has enabled us to make and use complex tools and develop complex language

– Capacity for _____________________: we communicate with complex spoken and written language

Biological Organization

• Atoms

• Molecules

• Cells

• Tissues

• Organs

• Organ Systems

• Organisms

• Populations

• Communities

• Ecosystems

Science

• Science is both a body of knowledge and a process

• The process of science (the way scientific knowledge is acquired) is generally called the _________________________

– A systematic way of formulating and testing hypotheses

– A ___________________ is an “educated guess”

– Hypotheses must be _________________

• Must be able to design an experiment or collect some data that may support or

refute the hypothesis

•

• The scientific method:

–Make an ________________

–Develop a _______________

–Make a ______________ based on the hypothesis

–Design and carry out an _______________ to test the hypothesis

• Experiment must be replicated and controlled

– Analyze data: do they support or refute the hypothesis?

•

•

• Controlled Experiments

– All possible variables must be controlled so they cannot affect the outcome

– ______________________ are variables that stand alone and aren’t changed by the variable you wish to measure (examples: time, age, drug treatment)

– ______________________ depend on the independent variables; for example,

growth may depend on time, or blood pressure may depend on the drug treatment

– A __________________ is a group to which the experimental treatment isn’t applied; it is used as a group against which you can measure the effects of the

experimental treatment

• In drug trials, a _____________________ is often given to the control group; a placebo is a “false treatment”

• Why do we use placebos? Why not just not give this group of people any drug at all?

•

•

• Figure 1.8: The steps in a controlled experiment

• Scientists publish the results of their experiments

– Peer-reviewed journals are subjected to scrutiny of experts in the field

–Must be approved before publication

– It may then be read by a vast audience of scientists, who further scrutinize the work

• A well-tested hypothesis becomes a __________

– Scientists use the word _____________ to mean a broad hypothesis that has been extensively tested and _______________ over time

– It is the highest status that a hypothesis can achieve

Reading Graphs

• Most graphs are plotted on two lines, or axes

• The horizontal axis is the __-axis

– The _____________ variable is plotted here

• The vertical axis is the __-axis

– The _____________ variable is plotted here

•

• Figure 1.9. Types of graphs, including a scatter plot, a line graph, and a bar graph

• Figure 1.10. How a split axis affects a graph. The split axis in graph b consolidates the graph and makes it take up less space, but it might mislead you into thinking the

number of cases of a disease has been rising steadily since 1910, instead of only

since 1960.

Activity 1

• Consider the data provided. What kind of graph do you think would be most

appropriate? Use the graph paper provided to draw a graph, making sure to label the x- and y-axes. Be sure to put the dependent variable on the y-axis and the

independent variable on the x-axis.

• Appreciate statistics

– Statistics is the mathematics of organizing and interpreting ___________

– Scientists use statistics to determine how much confidence they should place in information

–Most scientists accept experimental results if they would get the same outcome _____% of the time

– __________________ is an expression of confidence in the certainty of the

results; expressed as a +/- after the average

• For example, if a poll says that 52% of voters said they will vote for candidate

X, but the standard error is +/- 3%, then that means the actual percentage

may be between 49-55%

• Standard error is often given on bar graphs as lines extending above and below

the top of each bar

•

•

• Distinguish ______________ from scientific evidence

– An ______________ may take the form of a testimonial or a short unverified

report

– Cannot be generalized to the larger population because it isn’t based on empirical

evidence

– Just because a treatment worked for one person doesn’t mean it will work for most people

•

• Science improves technology and the human condition

– Think of all of the ways science has improved your life

• Cell phone? Air conditioning? Medicine? Etc.

• But science has limits

– Is limited to physical explanations of events in the natural world

– Science cannot address questions beyond the natural world (i.e. the spiritual)

– Science may provide us with tools, technology and knowledge, but issues of

morality, ethics and law may govern how we apply them

•

• Beware “______________” – when someone presents “evidence” in a way that

attempts to sound scientific, but which does not subject itself to the rigors of scientific testing

• Some signs of pseudoscience:

– No ___________ presented

– Relies solely on ______________ evidence

– Authors have a financial interest in their findings

– No testable _____________

–Often sounds “too good to be true”

• Bill Nye the Science Guy on “Pseudoscience” versus “Science”

•

– https://www.youtube.com/watch?v=_q8D2dhWPSs

• 5-minute break

Lec. 2, Part B: Chapter 3 – Structure and Function of Cells

• _______ – the lowest level structure that can perform all activities required for life

• The first scientist to observe cells was ________________ in __________

– Used a ___________________ to view cross sections through cork and other

tissues

– Prior to invention of microscopes, nobody could see cells

–When he observed that all organisms were composed of these little

compartments, he coined the term “_____”

• All living things are composed of cells

The Cell Theory (or Cell Doctrine)

1. ___________________________________

2. A single cell is the smallest unit that exhibits all of the characteristics of life

3. All cells come only from _____________________

•

• In most multicellular organisms like animals and plants, all cells in the body come

from a single cell, the __________

– A __________ is a fertilized __________

–During fertilization, the DNA from the sperm is united with the DNA from egg in

the egg’s nucleus

– The zygote then begins dividing by a process called _________, making identical

copies of itself

– An adult human has about 100 trillion cells

–Different types of cells (e.g. muscle cells, neurons, bone cells, etc.) look and

behave differently

Eukaryotic Cell Structure

• Living organisms can be categorized based on their cell types:

– ________________ cells lack membrane-bound organelles such as nuclei and

mitochondria, and tend to be smaller in size

• Two domains of life are prokaryotes: Bacteria and Archaea

– _____________ cells have membrane-bound organelles and tend to be larger in

size

• The third domain of life is called Eukarya, and includes the Kingdoms Plantae,

Animalia, Fungi and various Protists

• Humans are Eukaryotes, classified in Kingdom Animalia

• Our cells are therefore ___________

• Eukaryotic cells are surrounded by a ____________________________

• Within the membrane, eukaryotic cells contain the ______________, which consists

of a fluid called ____________, and various structures called _____________ which carry out specific functions

•

• Different cell types have different functions, so their structures may vary

• However, we will look at a “generic” animal cell to get an overview of the major

organelles found in eukaryotic cells and what their functions are

Animal Cell

• Nucleus

– Has a double membrane

– Contains ___________

• ___________ is attached to proteins, forming long fibers called chromatin

• Each fiber = a _______________

– Also contains a _____________ (produces ribosome parts)

•

• Ribosomes

– Small dots outside of nucleus

– Build _______________

– How?

– 2 Processes:

• _________________ (in nucleus: DNA mRNA)

• _________________ (in cytoplasm on ribosome:

RNA Protein)

• Ribosomes use coded instructions from the DNA to build proteins, and those instructions are carried to the ribosomes out in the cytoplasm on a molecule

called _____________

–

• Endoplasmic Reticulum (ER)

– Two types: Smooth ER and Rough ER

– __________ ER

• Looks “bumpy” due to presence of _______________

• Functions include

–Making more ________________

–Ribosomes produce proteins that get inserted into the membrane

–Cells in your mouth that secrete saliva have a lot of rough endoplasmic

reticulum, which produces the enzyme saliva

–Gets carried to cell surface and secreted

–Other proteins produced by these ribosomes may be packaged and transported to other parts of the cell

•

– _____________ ER

• Smooth appearance due to lack of ______________ found in the rough ER

• Enzymes built into the smooth ER allow it to carry out many functions, including

_______________________________

–So, cells in the testes and ovaries, which produce hormones testosterone and

estrogen, are rich in smooth ER

• In liver cells, the smooth ER helps ______________________

–A person’s liver cells will increase in smooth ER as they are exposed to more

of these drugs

–This can lead to “tolerance” to drugs, and potentially addiction

–Can also make certain drugs like antibiotics less effective

•

•

• ____________ Apparatus

– Refines, stores, and distributes ER products

•

LE 6-16-1

LE 6-16-2

LE 6-16-3

• Lysosomes and peroxisomes

– Lysosomes are safe location for digestion

• Little sac of ___________________

• (_____________ = proteins that catalyze (facilitate) a chemical reaction)

• Digest food, but also destroy harmful bacteria and “recycle” worn-out

organelles

– Peroxisomes take up ___________________ and degrade them into harmless

waste, which is excreted

–

•

•

• Vesicles

– Sacs that have budded from the ____________________ or

___________________

– Proteins in the vesicle membrane act like “shipping labels,” determining where the

products go

– ____________________ contain products that are destined to be excreted from the cell

• They fuse with the plasma membrane, emptying their contents to the outside of the cell

• Mitochondria (found in essentially all eukaryotes – plants, animals, protists and

fungi)

– The site of ______________________

• The process where energy is obtained from food molecules

• This energy is stored in a molecule called _____ (adenosine

________________)

• A cell that has a high rate of energy consumption, such as a muscle cell, may contain over 1,000 mitochondria

•

–Mitochondria have a smooth outer membrane, and an inner membrane with

numerous folds called ________________

– Proteins involved in the electron transport chain reactions are embedded in the cristae, providing a large surface area for creating ________

• ______ = a high energy molecule which cells use to do work

•

LE 6-17

• Cellular structures for support and movement

– A network of fibers in the cytoplasm called the ___________________ provides a framework for the plasma membrane of the cell (kind of like tent poles support a

tent)

–

•

• Cilia and Flagella

– Extend from some cells to allow them to move, or to move the solution around

the cell

– ___________ are shorter and usually more numerous than ___________

– Ciliated cell example: cells lining your windpipe

– Flagellated cell example: sperm cells

–

–

–

–

–

Cells are Surrounded by Plasma Membranes

– Fluid Mosaic Model of membranes

• Cell membranes are composed of a double-layer of ______________

• Within the phospholipids are embedded ______________ and _______________

•

– Phospholipids have a ___________ head and ___________ tails

• Polar phosphate heads face the watery solution on the inside and outside of the

cell

• Lipid tails and sandwiched in between (inside the membrane)

– _______________ increases the strength of the membrane, while maintaining its flexibility

– Various types of _____________ may act as doors or gates, regulating what goes

into and out of the cell

How Molecules Move Across the Plasma Membrane

• Not all molecules can move across a plasma membrane (depends on size and

characteristics of the molecule)

• The plasma membrane is _____________ permeable

• Two types of transport: _________ and __________

• ____________ transport require the cell to spend energy

• ____________ transport does not require energy

•

•

• Comparing solute concentrations of two solutions:

•

– ____________ = the solution with the greater concentration of solultes

– ____________ = the solution with the lower concentration of solutes

– ____________ = two solutions with equal solute concentrations

• Passive Transport

–Osmosis and Diffusion

• ___________= movement of water from an area of low solute concentration to an area of high solute concentration

–In other words, from ___________ to ___________ solutions

–The pressure required to offset osmosis is called __________________

•

• ________________ = movement of solute from area of high solute

concentration to low solute concentration

–In other words, from hypertonic to hypotonic solutions

•

•

•

Three Types of Passive Transport Across Cell Membrane

1. Diffusion through the lipid bilayer

– The lipid bilayer allows free passage of some molecules while restricting others

– Small, ____________ _____________ molecules can diffuse through the lipid bilayer easily

– ____________ or ______________________________ molecules can’t cross the

lipid bilayer because they aren’t soluble in lipids

– Two important lipid-soluble molecules are ______________ (which diffuses into

cells) and ____________________ (which diffuses out of cells)

–

•

• Diffusion through protein channels

–Water and many ions diffuse through protein channels

– These protein channels span the entire width of the plasma membrane

– The __________ and ___________ of the protein channel, as well as the electrical charges on various amino acid groups that line the channel, determine

which molecules can pass through them

– Some channels open all the time, others are “____________” meaning they can open and close

• Gated channels especially important in regulating transport of ions (sodium, potassium, and calcium) in electrically excitable cells like neurons and muscle

cells

• Facilitated transport (or facilitated diffusion)

–Molecules attach to a membrane protein called a ___________________

– This triggers a change in the shape or orientation of the ___________________

– This causes the molecule to be taken into the cell

–Once the molecule is released, the transport protein resumes its original shape

–Direction of movement is always from ____________ to ______________ concentration

–

–

• Passive transport always results in a molecule moving from an area where it is in

___________ concentration to where it is in ___________ concentration

• Active transport can move molecules from where they are in ________

concentration to where they are in ________ concentration (e.g., against the concentration gradient)

• Active transport uses ______________ and requires the cell to expend energy (ATP)

•

• The __________________ pump helps maintain cell volume

– To prevent excessive amounts of water from flowing into cells by osmosis, stretching and even bursting the cell membrane, sodium-potassium pumps help

get rid of unneeded ____________ ions and take in _____________ ions

• ___ Na+ ions expelled for every ___ K+ ions taken in

• Result: lowers the overall number of ions inside cell, reducing the concentration

of solutes in cyotosol

• This reduces osmotic pressure of water trying to move into cell by osmosis

• If a cell needs to reduce its volume, it can ______________ activity of sodium-

potassium pumps

–

Activity 2

1. Draw an animal cell with the following organelles included and labeled: nucleus,

nucleolus, mitochondria, smooth and rough endoplasmic reticulum, golgiapparatus, peroxisome, and lysosome

2. Define passive transport and name three passive transport methods used to transport different molecules across the plasma membrane

3. Barium is a toxic metal that can damage the sodium-potassium pumps of cells. It is used in rat poison, but sometimes people are exposed to high amounts (for

example, if the groundwater is polluted with barium that may leak from

electronics like flat screen TVs). If a cell’s sodium-potassium pumps are poisoned so that they stop working, will the cell swell, shrink, or stay the same?

4. Liver cells are responsible for, among other things, detoxifying the body (for example, getting rid of alcohol or drugs). Which two of the following organelles

would be especially abundant in liver cells?

– Nucleus, mitochondria, peroxisomes, lysosomes, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi apparatus

•

Cellular Respiration

• Cells use and transform matter and energy

• _______________ is the sum of all the chemical reactions in an organism

• Two types of metabolic pathways:

– ________________ – molecules assembled into larger molecules

– ________________ – large molecules broken down into smaller molecules

• Cellular respiration, in which glucose is broken down into water, carbon dioxide, and ATP, is a catabolic pathway

• We will only briefly discuss the main steps in cellular respiration:

– _______________

– ____________________

– _______________________ (aka ______ Cycle)

– ________________________

• The purpose of cellular respiration is to convert energy in large molecules into

energy stored in small, usable molecules called _____

How do organisms obtain energy from food?

– The energy stored in the bonds of food molecules is released when broken down in cellular respiration

– That energy is transferred to molecules called ATPs (adenosine triphosphate)

• Adenosine is an organic molecule; three _____________ charged phosphate groups are attached

•

•

– The phosphate groups repel each other and readily transfer from ATP to other

molecules

– This transfer of a phosphate group to another molecule is what causes cells to do

work

• ATP can do 3 kinds of work:

• It may cause a protein to contract (“_____________ work”)

• It may facilitate pumping of molecules across a membrane (“_____________ work”)

• It may facilitate a chemical reaction (“___________ work”)

–

LE 8-9

–When a phosphate group is lost from an ATP, the molecule become Adenosine ____________ (___)

– ATP is renewable, though – another phosphate group can be added back to the

ADP, making it ATP again

– The energy for restoring ATP from ADP is obtained through _____________________

• The first step of cellular respiration takes place in the _____________, but the remaining steps take place in the _____________

•

•

• Reaction occurs in the presence of oxygen

• ____________________________________

• Step 1: Glycolysis

•

• Step 2: Preparatory step

•

– Pyruvic acid from glycolysis is converted into _______________ – a 2-carbon

compound

– In the process, 2 _______________ molecules are given off

– The acetic acid combines with an enzyme called Co-a, making “___________”

– _____________ is the fuel of the Citric Acid Cycle

•

• Step 3: Citric Acid (Krebs) Cycle

–

–One turn of the cycle generates two molecules of ___________, one _____, three

molecules of ______, and one molecule of ____________

– The cycle occurs _________ for every glucose molecule, because two Acetyl-CoA’s are produced per glucose

– The NADH and FADH2 are used in the_____________________

Krebs Cycle (aka Citric Acid Cycle)

• Step 4: Electron Transport Chain

•

– So far, only 4 ATPs have been produced

– Cellular respiration can yield up to ____ ATPs, so the majority of them are

produced here

– _______ and _________ move to the inner membrane of the mitochondria and release their electrons to a chain of proteins embedded in the membrane (the

electron transport chain)

– Sequential transfer of electrons from protein to protein allows energy to be

released in manageable quantities

– ____ ions are transported from the inner compartment of the mitochondria to the outer compartment, leading to a concentration gradient

–When H+ ions diffuse down their concentration gradient, they must move through an ______________ protein; this is where ATP is produced

– A maximum of ____ ATPs may be produced here

•

– The electron transport system generates ATPs by __________________ – the

addition of a phosphate group to an ADP

– The process requires oxygen, so it is called ____________________________

– At the end of the electron transport chain, electrons have lost most of their energy, and they combine with H+ions and oxygen to make _________, another waste produce to cellular respiration

• Summary of cellular respiration:

– A multi-step metabolic pathway by which energy is extracted from large organic

food molecules (glucose)

– The most effective way to harvest energy from fuel is to do it slowly under controlled conditions

• For example, a car’s engine burns gasoline slowly, drop by drop in the pistons of the car, allowing energy to be converted to mechanical energy.

• In a similar way, cellular respiration releases the energy in glucose slowly by

breaking the bonds in glucose gradually and converting that energy to ATP

–

•

• All for today…

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