Final ExamFinal ExamLiving EnvironmentLiving Environment

Parts 2 and 3Parts 2 and 3

*note: Many of these concepts will *note: Many of these concepts will also appear on Part 1.also appear on Part 1.

Type of transport

Diffusion: substances move from high concentration to low.

Equilibrium: concentrations on both sides of the membrane are equal.

Diffusion vs. Active TransportDiffusion vs. Active Transport

Active Transport: substancesmove from low to high concentration; needs ATPenergy.

http://www.northland.cc.mn.us/biology/Biology1111/animations/transport1.html

Receptor ProteinsReceptor Proteins

Are part of the cell membraneAre part of the cell membranePick up specific molecules; puzzle-piece fit with Pick up specific molecules; puzzle-piece fit with signal molecules.signal molecules.Can be blocked by drugs Can be blocked by drugs and block the action of and block the action of the signal molecule.the signal molecule.

Cell membrane

Circulatory – blood transports nutrients/gases to cells; Circulatory – blood transports nutrients/gases to cells; wastes/gases from cells wastes/gases from cells (by diffusion),(by diffusion), pumped by the heart pumped by the heart musclemuscle

Respiratory – gas exchange Respiratory – gas exchange (diffusion)(diffusion) O O22 in, CO in, CO22 out, of blood out, of blood Digestive – breaks down foods to small molecules that diffuse Digestive – breaks down foods to small molecules that diffuse

into blood, and then into cells.into blood, and then into cells. Excretory - filters waste Excretory - filters waste (by diffusion)(by diffusion) from blood (sweat, urine, from blood (sweat, urine,

exhaled COexhaled CO22 Nervous and endocrine – interprets and reacts to signals from Nervous and endocrine – interprets and reacts to signals from

the environment, sends chemical messengers to all systemsthe environment, sends chemical messengers to all systems Immune – fights off pathogens and other invaders by Immune – fights off pathogens and other invaders by

recognizing and destroying themrecognizing and destroying them Reproductive – makes hormones & gametes; develops parent to Reproductive – makes hormones & gametes; develops parent to

be able to make and develop offspring; first system to shut be able to make and develop offspring; first system to shut down, not necessary for survival of organism itselfdown, not necessary for survival of organism itself

• Nervous system: only system which does not utilize the Nervous system: only system which does not utilize the circulatory system directly.circulatory system directly.

Human Systems – all function to Human Systems – all function to maintain homeostasis!maintain homeostasis!

Disease: When homeostasis is not Disease: When homeostasis is not maintainedmaintained

DiabetesDiabetes – blood glucose too high; not – blood glucose too high; not enough glucose getting into the cellsenough glucose getting into the cells Result – person’s blood sugar is too high/ no energy, Result – person’s blood sugar is too high/ no energy,

body begins to shut downbody begins to shut down Insulin – a hormone helps push glucose out of the Insulin – a hormone helps push glucose out of the

blood into the cells, so it can be used by the blood into the cells, so it can be used by the mitochondria to make ATP for energymitochondria to make ATP for energy

Treatment – insulin injections and/or dietary changesTreatment – insulin injections and/or dietary changes Result – blood glucose is in homeostasis. Result – blood glucose is in homeostasis.

Disease: When homeostasis is not Disease: When homeostasis is not maintainedmaintained

Sickle cell anemiaSickle cell anemia – a change in the DNA – a change in the DNA (mutation), resulting in abnormally shaped (mutation), resulting in abnormally shaped hemoglobin proteinhemoglobin protein CauseCause – two mutant genes for sickle-shaped – two mutant genes for sickle-shaped

RBCsRBCs EffectsEffects – a person’s circulation is poor; RBCs – a person’s circulation is poor; RBCs

get stuck in the capillaries. There is pain.get stuck in the capillaries. There is pain. Adaptive Value in the EnvironmentAdaptive Value in the Environment – –

Heterozygous individuals are resistant to the Heterozygous individuals are resistant to the parasite that causes malaria.parasite that causes malaria.

Pathogens can cause disease.Pathogens can cause disease.How can we fight pathogenic disease?How can we fight pathogenic disease?

Use of antibiotics and other chemicalsUse of antibiotics and other chemicals Use of mutagenic agents (substances causing mutation) Use of mutagenic agents (substances causing mutation)

ex: radiationex: radiation

What makes treatments work?What makes treatments work? DNA of pathogen is disabledDNA of pathogen is disabled Reproduction of pathogen is haltedReproduction of pathogen is halted Cell dies or fails to reproduceCell dies or fails to reproduce

Why do antibiotics fail?Why do antibiotics fail? Bacteria mutate and antibiotic-resistant strains evolve, survive, Bacteria mutate and antibiotic-resistant strains evolve, survive,

reproduce and pass their resistance onto their offspring.reproduce and pass their resistance onto their offspring.

Enzymes Affect the Rate of Enzymes Affect the Rate of Chemical ReactionsChemical Reactions

The rate at which an enzyme can function is affected by temperature and pH.As with many other molecules, enzymes have a specific shape. This enables them to react with specific molecules. All enzymes are proteins and therefore are coded for in an organism's DNA. (names end in “ase”)

Kinds of EnzymesKinds of Enzymes(biological catalysts)(biological catalysts)

Hydrolysis EnzymesHydrolysis Enzymes (break down) (break down) Smaller molecules produced for diffusion, to release energy Smaller molecules produced for diffusion, to release energy

found in chemical bonds, or to recycle building blocks of found in chemical bonds, or to recycle building blocks of molecules.molecules.

Cellular respiration and digestion use hydrolytic enzymes.Cellular respiration and digestion use hydrolytic enzymes.

Dehydration Synthesis EnzymesDehydration Synthesis Enzymes (put together) (put together) Larger molecules are produced (ex: pigments, antibodies, Larger molecules are produced (ex: pigments, antibodies,

hormones, nucleic acids, etc.hormones, nucleic acids, etc. Photosynthesis, DNA replication, and protein synthesis use Photosynthesis, DNA replication, and protein synthesis use

synthesis enzymes.synthesis enzymes. How enzymes work: How enzymes work:

http://www.lewport.wnyric.org/jwanamaker/animations.htmhttp://www.lewport.wnyric.org/jwanamaker/animations.htmClick on enzyme activity.Click on enzyme activity.

All animal life on Earth (including humans) depends on the oxygen

produced by photosynthesis!

Plants absorb carbon dioxide from the air. Too much carbon dioxide will

cause the Earth to heat up(the greenhouse effect).

Animals can eat the sugar made to use as energy

chloroplasts

Energy rich organic compounds.

PhotosynthesisPhotosynthesis

Cellular RespirationCellular Respiration

Oxygen from the environment.

MitochondriaGlucose

WaterWater

Carbon Carbon DioxideDioxide

Energy Energy (ATP)(ATP)

Energy is stored in the bonds of the ATP molecule. This is the energy source for all life processes.

Glucose (sugar) is used to produce high energy storage molecules known as ATP.

Respiration occurs continuously in the cells of all organisms.

Compare and ContrastCompare and Contrast Photosynthesis & Cell Respiration.Photosynthesis & Cell Respiration.PhotosynthesisPhotosynthesis

1.1. ChloroplastChloroplast

2.2. Carbon dioxide and Carbon dioxide and waterwater

3.3. GlucoseGlucose

4.4. Glucose is used Glucose is used as for cell respiration.as for cell respiration.

5.5. Oxygen gas is used Oxygen gas is used for cellular for cellular respiration.respiration.

Cell RespirationCell Respiration

1.1. MitochondriaMitochondria

2.2. Glucose and oxygenGlucose and oxygen

3.3. ATPATP

4.4. ATP supplies energy ATP supplies energy for all life processes.for all life processes.

5.5. Carbon dioxide gas is Carbon dioxide gas is used for used for photosynthesis.photosynthesis.

organelle used?organelle used?

resources resources needed?needed?

energy rich energy rich molecule molecule produced?produced?

How is energy How is energy rich molecule rich molecule used?used?

How is gas How is gas produced used?produced used?

Cloning Racehorses...Cloning Racehorses... What is the advantage of having a cloned racehorse?What is the advantage of having a cloned racehorse? How do cloned individuals differ from those normally How do cloned individuals differ from those normally

reproduced?reproduced? What would be a disadvantage of producing these What would be a disadvantage of producing these

clones?clones? Why could not a breeder mate these horses with Why could not a breeder mate these horses with

each other to produce a super fleet of racehorses?each other to produce a super fleet of racehorses? If a horse breeder decided to mate a clone with an If a horse breeder decided to mate a clone with an

unrelated horse, why would the offspring not be unrelated horse, why would the offspring not be identical to either parent?identical to either parent?

Humans Impact on the EcosystemHumans Impact on the Ecosystem(ex: through genetic engineering)(ex: through genetic engineering)

Example:Example: Genetically engineered corn that Genetically engineered corn that produces its own pesticideproduces its own pesticide advantage:advantage: kills off bugs that would eat the kills off bugs that would eat the

corncorn disadvantage:disadvantage: bugs may develop resistance bugs may develop resistance

to the pesticideto the pesticide Danger of use of genetically engineered corn:Danger of use of genetically engineered corn:

pesticide may cause human diseases or pesticide may cause human diseases or mutations.mutations.

Pyramid of Energy Pyramid of Energy Heat is lost by the organism during metabolism.

What is the major factor driving evolution in all What is the major factor driving evolution in all organisms?organisms?

Changing environmental conditionsChanging environmental conditionsClimate affects resources >> affects survival of the fittestClimate affects resources >> affects survival of the fittest

Why?Why? Only those most successful in a changing environment survive.Only those most successful in a changing environment survive.

What is meant by a “stable environment”? (unchanging) What is meant by a “stable environment”? (unchanging)

Which is more likely to show evolution – a stable or Which is more likely to show evolution – a stable or unstable environment?unstable environment?

Evolution…change over timeEvolution…change over time

Evolution…change over timeEvolution…change over time

Caused by mutations in a changing Caused by mutations in a changing environment.environment. Variations in living things are caused by sexual Variations in living things are caused by sexual

reproduction & mutations (small genetic differences in reproduction & mutations (small genetic differences in DNA). DNA).

This variation leads to differences in adaptations.This variation leads to differences in adaptations. Favorable adaptations can lead to being more Favorable adaptations can lead to being more

successful (fit) at competition.successful (fit) at competition. Unfavorable adaptations can lead to being less Unfavorable adaptations can lead to being less

successful (fit) at competition.successful (fit) at competition. Those fittest to their environment survive, reproduce Those fittest to their environment survive, reproduce

and pass their “fit” DNA to their offspring.and pass their “fit” DNA to their offspring.

Comparing DNA Using Gel Comparing DNA Using Gel ElectrophoresisElectrophoresis

http://www.lewport.wnyric.org/jwanamaker/animations.htmhttp://www.lewport.wnyric.org/jwanamaker/animations.htm (Click on gel electrophoresis.)(Click on gel electrophoresis.) How can one determine which individual is the How can one determine which individual is the

closest match?closest match? Why are molecular similarities a more reliable Why are molecular similarities a more reliable

means of determining relationships among means of determining relationships among species than looking at physical similarities?species than looking at physical similarities?

Name a physical characteristic that vastly Name a physical characteristic that vastly different animals share? Flowering plants?different animals share? Flowering plants?

1.1. Gather information.Gather information.2.2. State title as a question. “Does … Effect …?”State title as a question. “Does … Effect …?”3.3. State hypothesis as an “If…then …” statement.State hypothesis as an “If…then …” statement.4.4. List materials and procedure using control and List materials and procedure using control and

experimental setups, changing only one variable.experimental setups, changing only one variable.5.5. Collect and organize data from a large sample of Collect and organize data from a large sample of

test subjects.test subjects.6.6. Conclude whether hypothesis was proven/not Conclude whether hypothesis was proven/not

proven.proven.7.7. State sources of error in procedure.State sources of error in procedure.8.8. Repeat the experiment making any needed Repeat the experiment making any needed

alterations to procedure. alterations to procedure.

9.9. Note:Note: The control group The control group is the one that receives is the one that receives no experimental treatment.no experimental treatment. (the group without ____)(the group without ____)

Designing a controlled experimentDesigning a controlled experiment

Independent Variable “X” Independent Variable “X” Has an effect on the dependent variableHas an effect on the dependent variable Is the manipulated variable, the one that changes Is the manipulated variable, the one that changes

between the experimental and control groupsbetween the experimental and control groups

Dependent Variable “Y” Dependent Variable “Y” The variable that is measuredThe variable that is measured Is affected by the changes in the independent variable Is affected by the changes in the independent variable

(“X affects Y”) (“X affects Y”)

Independent and Dependent Independent and Dependent VariablesVariables