Biology Characteristics of Life:

1. Living things are composed of cells. 2. Living things have different levels of organization. 3. Living things use energy. 4. Living things respond to their environment. 5. Living things adapt, grow and reproduce. 6. Living things reproduce. 7. Living things adapt to their environment.

Organic Compounds:

A compound is a combination of 2 or more atoms.

An organic compound is a compound that contains carbon atoms that have combined with each other.

An inorganic compound is a compound with no combination of carbon atoms.

The Four Types of Organic Compounds The Molecules of Life:

1. Carbohydrates:

Sugars (saccharides)

used for short term

energy.

2. Lipids: Fats and oils

used for long term

energy & insulation.

3. Proteins: Made up of amino

acids; used for construction

materials and chemical

reactions in the body. DNA

holds the message for

making all proteins.

o Enzymes:

Special types of proteins that speed up (catalyze) chemical reactions in the body but are not changed by the reactions.

4. Nucleic acids: DNA and RNA; contains genetic

information and instructions for making proteins.

Cell Types and Organelles

Cell - is the smallest unit that is alive and can carry on all the

processes of life.

Prokaryotic: cell that does not have a nucleus or

other membrane-bound organelles. Unicellular.

Eukaryotic: cell that has a nucleus and other

membrane-bound organelles. Uni/Multicellular.

Organelles: specialized structures that carry out a

specific function (job).

Organelle

Function

Plant

Animal

Bacteria

Nucleus

Controls center; contains chromosomes made of DNA

Mitochondria

Cell respiration; provides energy, power and heat (ATP)

Endoplasmic

Reticulum

Transports substances through the cell

Golgi body

Sorts, modifies, cell products/proteins

Ribosome

Protein synthesis/Makes proteins

Lysosome

Contains digestive enzymes to break down and digest waste and old organelles

Cell

Membrane

Maintains homeostasis by controlling what enters and leaves the cell. Protection.

Cell Wall

Support and Protection

Chloroplast

Traps sunlight to make food for the plant through Photosynthesis

Vacuole

Stores water.

Cytoplasm

Suspends organelles in a cell; enclosed within the cell membrane

Organic Compounds

Cell Membrane

-Made up of biomolecules called phospholipids (fats that don’t like water). -Phospholipid bilayer is the 2 layers of phospholipids that make up the cell membrane. -Selectively permeability, which means that it allows some, but not all materials to cross.

Cellular Transport

Homeostasis: ability of cell, system, organism to maintain stable

internal equilibrium. (temperature, pH, water content). Cell Transport: movement of molecules across the cell

membrane.

Transport through the Cell Membrane

Transport

Movement of molecules

Requires Energy from

Cell?

Passive High to low concentration No

Active Low to high concentration Yes

Passive transport: requires no energy, moves with concentration

gradient (high to low).

Diffusion: movement of molecules from high to low

concentration.

Osmosis: diffusion of water across a selectively

permeable membrane, from high to low, until equilibrium is reached.

Facilitated diffusion: the movement of molecules from

high to low concentration, but requires a channel protein to help the molecule across.

Active transport: requires energy, moves against the

concentration gradient (low to high).

Types of solutions:

Hypotonic solutions cause water to move into the cell causing the cell to swell.

Hypertonic solutions cause water to move out of the cell causing the cell shrivel or die.

Isotonic solutions cause water molecules to move into and out of the cell at an equal rate; cell size does not change.

MEASUREMENT

Cellular Energy

Photosynthesis: radiant energy from the sun is used by

producers to join carbon dioxide and water to make food (glucose); process takes place in the chloroplast. Photosynthesis: 6CO2 + 6H2O C6H12O6 + 6O2

Cellular Respiration: mitochondria break down food molecules

(glucose) to produce cell energy (ATP).

Cellular Respiration: C6H12O6 + 6O2 6CO2 + 6H2O + ATP (energy)

Reactant(s) Product(s) Organelle Involved

Photosynthesis -Carbon dioxide (CO2) -Water (H2O)

-Glucose (C6H12O6) -Oxygen (O2)

Chloroplast

Cellular Respiration

Glucose (C6H12O6) -Oxygen (O2)

-Carbon dioxide (CO2) -Water (H2O) -ATP

Mitochondria

ATP: made of adenosine molecule, ribose sugar, and three

phosphate groups; all held together by chemical bonds. ATP Cycle:

Remember that when bonds are made = ENERGY STORED

When bonds are broken = ENERGY RELEASED

So the way energy is stored and released with ATP is to add or remove a phosphate.

.

The cell cycle is the phases in the life of a cell consisting of cell growth and division:

Process starts with diploid cells and ends with diploid cells.

- Diploid – two sets of chromosomes – 2n

Before mitosis: Chromosomes have copied themselves.

Sister chromatids: original chromosome and its exact

copy are attached to each other. Phases of mitosis

Cell Specialization: DNA holds the genetic information that

controls what a cell can do and what molecules it can make. Example: White blood cells in animals are specialized to attack pathogens like viruses or bacteria.

Cell Differentiation: process by which a cell becomes specialized

for a specific structure or function during multicellular development.

DNA and Replication

Nucleotides: structures that make up nucleic acids (DNA/RNA)

DNA

Sugar Deoxyribose

Bases Adenine, Thymine, Guanine, Cytosine

Base Pairs A T

C G

Shape Double Helix

Function Codes for proteins/RNA

Replication: the process used by cells to copy DNA; takes place

during the S phase of the cell cycle.

The enzyme, Helicase, unzips DNA and each side of the ladder acts as a template for the building of the new half.

The enzyme, DNA Polymerase, bond the new nucleotides together.

EX) TACGGAC (old strand) ATGCCTG (new strand

DNA RNA

Sugar Deoxyribose Ribose

Bases Adenine, Thymine,

Guanine, Cytosine

Adenine, Uracil,

Guanine, Cytosine

Base

Pairs

A T

C G

A U

C G

Shape Double Helix Single Strand

Function Codes for proteins/RNA

Copy of DNA

information for

transcription

Cell Cycle

Phase Steps in Phase

Interphase

G1: intense growth and enzyme production S: DNA synthesis/replication G2: growth and preparation for cell division.

Mitosis

M: Division of a cell into 2 identical daughter

cells (PMAT)

Transcription: process that copies DNA’s genetic information into

messenger RNA: 1. DNA strands temporarily unwind. 2. Complementary RNA nucleotides pair up with one strand

of DNA nucleotides. 3. Messenger RNA (mRNA) carries specific protein

synthesis instructions to ribosomes. EX) TACGGAC (template DNA strand) AUGCCUG (RNA built) Codon: formed from a sequence of three nucleotides (like AAA or

GAC); different codons specify one of twenty different amino acids. Translation: process by which a protein is made from mRNA;

occurs within a cell’s ribosomes; tRNA (transfer RNA) matches codons to amino acids which then join together to form a protein chain.

Protein: molecule made of amino acids that performs a specific

task.

Codon Chart

Mutation: genetic change in DNA.

There are many kinds of mutations that occur at different levels, but they all change DNA.

At the DNA level during Replication.

At the Chromosome level during Meiosis and Mitosis. Point mutations effect single bases

Substitution Frameshift mutations shift the “reading frame” of the DNA.

Insertion

Deletion

Mutations can be harmful, beneficial or have no effect on the organism.

A mutation that changes codon AAA to codon AAG (substitute G for the last A) likely has no effect because AAA and AAG both code for Lysine.

A mutation that results in codon UAA would likely result in an observable change because UAA is a stop codon.

Meiosis: Cell division that produces gametes (sex cells), such as

sperm and egg cells.

Haploid – cell with half the number of chromosomes - n Steps in meiosis 1. Before meiosis:

2 chromosomes of the same type come together to make a chromosome pair.

Each chromosome doubles (DNA replication during S phase of Interphase).

This gives 4 chromosomes stuck together.

2. Meiosis I: Chromosome pairs separate into two new cells-

PMAT 3. Meiosis II: Each chromosome separates from its copy into 4

new cells- PMAT

In meiosis, one cell becomes four non-identical daughter cells. BUT in mitosis, one cell becomes two daughter cells.

Chromosomes: DNA strands in the nucleus that contain the

directions on how to make and keep an organism alive. Copied and passed from parent to offspring. Crossing over occurs during Meiosis, pieces of chromosomes are

exchanged.

Protein Synthesis Mutations and Genetic Variations

Translation

Transcription

Fertilization: Process of an egg and a sperm cell combining to

produce a zygote, both haploid cells.

Zygote: Baby that is only 1 cell big

Human egg cell (23 chromosomes) + Human sperm cell

(23 chromosomes) = baby (46 chromosomes)

Autosomes: Chromosomes that do not determine gender

(chromosomes 1 through 22) Sex chromosomes:

Chromosomes that determine gender (chromosome 23)

Females are XX, Males are XY

GENETICS

Genetics: the study of heredity.

Gregor Mendel is an Austrian monk credited with beginning the study of genetics.

Gene: segment of DNA; controls specific traits.

Humans have 2 genes for every trait. Heredity: passing on of characteristics from parents to offspring.

Alleles: Different forms of a single trait, like blue and brown are

two eye color alleles.

Dominant gene: Allele that is expressed when two different

alleles are present in an organism’s genotype.

Represented by a capital letter.

Recessive gene: Allele that is expressed only when two copies

are present.

Represented by a lowercase letter.

Homozygous (purebred): When 2 genes are alike for a trait.

BB is homozygous dominant; bb is homozygous

recessive.

Heterozygous (hybrid): When 2 genes are different for a trait.

Bb is heterozygous.

Phenotype: The physical appearance of an organism (Brown

eyes), like a picture - what it looks like on the outside. Genotype: Includes both of the genes that code for a trait;

represented by the letters. Example: BB, Tt, Rr

Mendelian Genetics: Laws regarding the inheritance of genetic

traits: 1. Law of Segregation: alleles segregate and recombine;

one allele is inherited from each parent. 2. Law of Dominance: one trait may mask (dominant) the

effect of another trait. 3. Law of Independent Assortment: allele for a trait

segregate and recombine independently of other traits; example: height and eye color do not influence each other.

Monohybrid Cross: One trait

G = dominant allele for yellow g = recessive allele for green

Dihybrid Cross: two traits

G and R = dominant allele for yellow and round g and r = recessive allele for green and wrinkled.

Non-Mendelian Inheritance: inheritance pattern that does not

follow Mendelian genetics law. Incomplete Dominance: One allele is NOT completely dominant

over the other. R = dominant (incomplete) allele for red flower r = recessive allele white flower

Co-Dominance: Both alleles are dominant; both alleles are

expressed. R = dominant allele for red coat W = dominant allele for white coat

Sex-Linked Inheritance: Allele for a trait is carried on only one of

the sex chromosomes.

The gene for male-pattern baldness is linked to the x chromosome. XB = female sex chromosome with dominant baldness allele Xb = female sex chromosome with recessive baldness allele (carrier) Y = male sex chromosome does not carry baldness allele

Biotechnology DNA Fingerprinting: process of identifying the location of base

pairs at certain locations on the DNA for comparison to a known sample. Gel Electrophoresis: is a process of passing DNA fragments

through agar gel to separate the fragments by size.

Karyotypes: pictures of chromosomes that can be counted and

sorted. Chromosomes from a single cell are isolated in a solution and used to create the Karyotype, which can determine if a person

has an abnormal number of chromosomes and the location of the abnormality

Nondisjunction mutations: (monosomy and trisomy) can result in Down Syndrome, Kleinfelter’s Syndrome and Turner’s Syndrome

Genetic Recombination: At times, either biologically or artificially,

it is useful to combine certain segments of DNA from other organisms.

Evolution and Natural Selection

Evolution: Genetic change in a species over time. Changing of a

species’ (not an individual’s) traits over many, many years; natural selection is a mechanism for evolution. Natural Selection: process by which organisms with certain

favorable traits survive and reproduce more successfully than others; causes change in populations (NOT individuals) and affects the diversity of a species.

Example: insects that are resistant to insecticide are

more likely to survive and reproduce.

Adaptation: inherited trait that gives and advantage to individual

organisms and is passed on to future generations. Traits: Characteristic that is inherited.

Behavior: the way an organism moves, functions or reacts.

Behavior Description Example

Inherited Born with it; not learned Breathing

Learned Not born with it; must learn Reading

Evidences of Evolution

1. Fossil Record: preserved remains or traces of

organisms.

2. Homologous Structures: same basic structure formed

from same embryonic tissue.

3. Analogous Structures: same basic functions due to

same environmental pressures.

4. Embryology: embryos of various species appear

identical.

5. Molecular Homology: DNA and protein amino acid

sequence comparisons. Strongest evidence for Evolution. EX: the human genome and the chimpanzee genome are approximately 99% identical.

6. Biogeography: geographic distribution of organisms;

species that live in the same area are more closely related, but related species can also be found living far apart.

Evolutionary Mechanism

Description Effect on Genetic

Variation

Genetic Drift

Change in green pool caused by chance. EX: catastrophic event; flood, volcano, mass isolation of groups, hunting.

Gene Flow

Change in gene pool caused by organisms’ gradual movement into or out of the population.

INTO population

OUT of population

Mutation

Change in gene pool caused by insertion, deletion, or substitution of DNA sequence of gamete cell.

Recombination

Change in gene pool caused by exchange of genetic sequence during gene crossover events during Prophase I of meiosis.

Taxonomy: the study of the methods of man-made classification

systems. Classification: way of organizing information by putting objects or

ideas into groups based on similarity.

Enables us to study relationships and differences Example: Man’s best friend, the dog.

General Specific

Kingdom Characteristics

Archaebacteria Ex: halophiles, methanogens

prokaryotic, cell wall, no nucleus; lives in extreme environments

Eubacteria Ex: bacteria, algae

prokaryotic, cell wall, no nucleus; autotrophs or heterotrophs

Protists Ex: amoebas, paramecium

eukaryotic, nucleus and cell membrane; autotrophs or heterotrophs

Fungi Ex: yeasts, mushrooms

eukaryotic, cell wall, nucleus, cell membrane; no chloroplasts, heterotrophs

Plantae Ex: mosses, ferns, trees

eukaryotic, cell wall, nucleus, cell membrane, chloroplasts, autotrophs

Animalia Ex: worms, fish, insects, bird, dog

eukaryotic, nucleus, cell membrane, heterotrophs

Binomial Nomenclature: modern classification system using a

two-word (genus and species) naming system; written in italics. Genus species Ex: Homo sapien human Phylogenetic Tree: diagram taxonomist use to show evolutionary

relationships among species Cladogram: diagram based on patterns of shared, derived traits

that shows the evolutionary relationship between groups of organisms.

Dichotomous Key: Guide used to identify organisms. Uses pairs

of observable traits as a checklist to pinpoint the organism’s identity.

Taxonomy & Classification

Kingdom Animalia

Phylum Chordata

Class Mammalia

Order Carnivora

Family Canidae

Genus Canus

Species lupus

Virus: microscopic (smaller than bacteria) nonliving particle that

can only reproduce in host cell and causes diseases/conditions like smallpox, colds, influenza (flu), HIV, warts Is made up of a capsid head/protein coat (containing DNA or RNA) and a tail that attaches to the host cells. Host: a living cell in which a virus reproduces.

Comparison Virus Cell

Classification Nonliving Living

Structure Head has nucleic acids surrounded by protein coat

Has nucleic acids, ribosomes, cytoplasm, etc.

Metabolism None; depends on host cell

Makes own proteins

Reproduction Needs host cell; does not grow

Divides into two similar cells after growth

Interactions Among Systems in Animals

Function Examples of Interactions

Regulation

The endocrine system makes hormones. Blood in the circulatory system carries the hormones to the skeletal system to control the amount of calcium released from bones.

Nutrient Absorption

Food is broken down in the stomach mechanically by the muscular system and chemically by water, acid, and enzymes in the digestive system. Nutrients are then absorbed by blood in the circulatory system.

Reproduction Certain hormones produced in the endocrine system control ovulation in the female’s reproductive system.

Defense

Mucus in the lungs traps a virus in the respiratory system. T-cells in the immune system destroy virus-infected cells. Nerves in the nervous system sense the need to cough.

Interactions Among Systems in Plants

Function Examples of Interactions

Transport The roots uptake water. Xylem tissues transport water to the leaves. Phloem tissue transport sugar and nutrients throughout the plant.

Reproduction

The reproductive organs in a flower are the pistil (female) and the stamen (male). A seed is a mature, pollinated ovule (fertilized egg). Hormones in a plant’s roots help trigger the growth of a seed.

Response

If light hits on one side of a stem, auxins (hormone) will build up in the cells on the shaded side of the stem. These cells then elongate and grow longer, causing the stem to bend toward the light.

Homeostasis: the regulation and maintenance of constant internal

conditions in and organism. Internal Feedback Mechanisms: self-regulating process, like a

chemical reaction, that can help maintain homeostasis. Positive Feedback: increases the effect in response to a stimuli.

EX: blood clotting after a cut. Blood clotting happens once the sensory for it has been triggered and the brain sends information to start blood clotting. Once blood clotting starts it sends information for more clotting factors.

Negative Feedback: decreases the effect in response to a

stimuli. EX: maintenance of normal body temperature.

Living things are affected by biotic and abiotic things in the

environment

Abiotic factor: the nonliving parts of an organism’s environment.

EX: air currents, temperature, light, and moisture

Have effects on living things and often determine which species can survive in an area.

Biotic factor: the living things that inhabit an environment.

EX: plants, animals, fungus, bacteria

all organisms depend on others directly or indirectly for food, shelter, reproduction, or protection

Levels of Organization

Species Population Community Ecosystem Biosphere Species: a group of similar organisms that can interbreed and

produce fertile offspring. Population: a group of the same species, that lives in one area.

Members of the same population may compete with each other for resources.

Some may have adaptations to reduce competition.

VIRUSES AND BACTERIA

Interactions Among Systems in Plants and Animals

Ecology

Community: a group of different species that live together in one

area. EX: a group of alligators, birds, fish, and plants that live together in Armand Bayou. A change in one population in a community may cause changes in the other populations. Ecosystem: includes all of the organisms as well as the climate,

soil, water, rocks and other nonliving things (abiotic factor) in a given area. Types of ecosystems:

Terrestrial ecosystems – located on land (forest, meadow)

Aquatic ecosystem – freshwater (ponds, lakes, river) and saltwater (ocean, marine)

Ecosystem Stability: changes in the environment, caused by

nature or humans, can affect the stability of an ecosystem in positive or negative ways. Environmental changes can help sustain diverse and abundant populations over a long period of time, or they can diminish or destroy populations.

EX: Human Impacts including air/water pollution or conservation

Limiting Factors: conditions

that control a population’s size (food, water, living space, disease, predators, etc.). Carrying Capacity: maximum

population that can live in area over given period of time; controlled by limiting factors.

Nutrition and Energy Flow

The ultimate source of energy for life is the sun! Autotroph/Producers: an organism that uses the suns energy to

make food energy in a process called photosynthesis. EX: grass, trees, green algae

Heterotroph/Consumer: an organism that must obtain nutrients

by eating others.

Herbivores – Only feed on autotrophs; eats plants.

Carnivores – Only feed on other heterotrophs (meat).

Scavengers – Eat animals that have already died.

Omnivores – Eat autotrophs and other heterotrophs.

Decomposers – Break down the complex compounds of

decaying plant and animals.

Community Interactions

Mutualism – a relationship in which both species benefit.

+/+ A bee pollinating a flower.

Commensalism – a relationship in which one species

benefits and the other species is unaffected. +/≠ Barnacles on a whale.

Parasitism – a relationship in which a member of one

species benefits at the expense of another species (the host). +/- Heartworms in a dog.

Matter, in the form of carbon, nitrogen, and other elements, flow through the levels of an ecosystem from producers to consumers. Food Chain: shows how energy and matter move from one

organism to another; energy originates from Sun; arrows show the direction of energy flow. Food Web: shows many food chains in an ecosystem; size limited

by amount of energy that can be transferred. Trophic Levels: classification of organisms by feeding

relationships; organisms (like omnivores) may appear in multiple levels.

Level Description Example Energy

First Producer Plants Most

Second Primary consumer Herbivores

Third Secondary consumer

Carnivores that eat herbivores

Fourth Tertiary consumer Carnivores that eat carnivores Least

Energy Pyramid: shows how energy is lost from one trophic level

to the next (energy for metabolism etc.); only about 10% of energy transfers to next level; therefore approximately 90% is lost as heat. Max of 4 to 5 trophic levels per pyramid; energy moves in one direction only (not recycled).

Biological magnification: The increasing concentration of a

substance, such as a toxic chemical, in the tissues of organisms at higher levels in a food chain.

As a result of biomagnification, organisms at the top of the food chain generally suffer greater harm from a persistent toxin or pollutant than those at lower levels.

Role of Microorganisms

Beneficial Bacteria: helpful bacteria are used to make

yogurt, cheese, and drugs like insulin; decompose and recycle nutrients (nitrogen cycle); help absorb nutrients during digestive process; used to tan leather; etc.

Harmful Bacteria: harmful bacteria can spoil food or

cause diseases like streptococcus (strep throat).

Roles of Organisms

Energy in an Ecosystem

Cycles in Nature

Carbon Cycle: the movement of carbon through the environment.

Plants use CO2 to make sugars and starches via photosynthesis.

Animals eat plants and use this carbon for cellular respiration.

Ecological Succession:

Nitrogen Cycle: constant movement of nitrogen through the

environment.

Bacteria change the atmosphere’s nitrogen gas (N2) into a usable form, like nitrates.

Plants uptake nitrates from the soil; plants are then eaten by animals.

Decomposers return nitrogen to the soil by breaking down dead organisms and/or waste.

Denitrifying bacteria change nitrogenous compounds back to N2