AP Biology Notes/Review <3 (ALL 8 UNITS)

Unit 1 - Water and Life ✓

https://docs.google.com/presentation/d/11PdEfOsShrBiYMjP0EEweFGjjrDLUU9pTHIeY_lkMmo/edit#slide=id.p2

Water

• Makes life possible on Earth

• Organisms are mostly made of water

• Liquid, solid, or gas

Hydrogen Bonding

• Because oxygen is more electronegative, it hogs electrons, making H2O a polar covalent bond

• Oxygen has a partial negative charge (𝛿-) and hydrogen has a partial positive charge (𝛿+)

• Water molecules will form hydrogen bonds with one another

  • Oxygen attracted to the Hydrogen (diff water molecules)

• Hydrogen bonds between water molecules are constantly breaking and reforming

• Hydrogen bonds are ~ 1/20 the strength of covalent bonds

Properties of Water

• 4 important properties of water that make it so good for supporting life

  • Cohesion

  • Temperature moderation

  • Floating of ice on liquid water

  • Use as a solvent

Cohesion hydrogen bonds hold water molecules together

• Helps plants to transport water up through their roots against gravity

• Water evaporates from leaves → more water moves up the vessels in the plant

• Causes water molecules to pull other water molecules up the plant

• Adhesion, the phenomenon of one substance sticking to another, also helps the water cling to the sides of the vessels

Surface Tension is the measure of the force necessary to stretch or break the surface of a liquid

• Water has a large surface tension because its hydrogen bonds resist stretching and breaking

• How mosquitoes and other animals are able to stand on water

Water’s High Specific Heat is the measure of how much heat it takes to cause a substance to change its temperature

• Due to hydrogen bonds

• A large body of water can absorb a large amount of heat from the sun and only get warm a couple of degrees

  • Coastal area = stable temperature

• Because living things are composed largely of water, they resist temperature change well

Heat of Vaporization the quantity of heat a liquid must absorb for one gram of it to be converted from liquid to gas

• Evaporation = liquid is transformed into a gas

• Water = high heat of vaporization

  • This is due to the need to break hydrogen bonds
    between water molecules to convert the water
    to a gas

  • Helps moderate the climate

  • Lots of the sun’s heat gets absorbed by water, moderating the temperature

Evaporative Cooling as liquid evaporates, the surface of the liquid left behind is cooled

• The most energetic molecules, therefore the ones with the most heat, are the most likely to evaporate

• Mammals utilize evaporative cooling in the form of sweating

• Plants utilize evaporative cooling as water evaporates from their leaves

Floating Ice

• Oceans and lakes don’t freeze solid because ice freezes on liquid water

• Ice is less dense than water, due to the fact that the water molecules are locked into a crystal lattice when frozen

• The frozen ice on top of the cold liquid water insulates the water below, allowing life to flourish below

Water as a solvent

• Solution a liquid that is a completely homogenous mixture of two or more substances

• Solvent what the dissolving

• Solute is a substance that is dissolved

• Aqueous solution in which water is the solvent

• Water is a very versatile solvent due to the fact that water molecules are polar

• Each dissolved ion is surrounded by water molecules, forming a hydration shell

Hydrophilic water loving

• Substances have lots of ionic and polar bonds, making them able to interact well with water

Hydrophobic water-fearing/hating

• Substances that are nonionic and have nonpolar bonds

• Water molecules can’t form hydrogen bonds with hydrophobic substances

• Oils are hydrophobic because it’s nonpolar

Wet Chemistry

• Called this due to reactions involving solutes dissolving in water

• Chemical reactions depend on the concentration of different solutes in water

Molarity the concentration of a material in a substance (M)

• A solution with a molarity of 1 has one mole of substance dissolved in 1 liter of water

Hydrogen Ions

• H2O ←→ H- + OH-

• This dissociation is very rare, but very important in the chemistry of life

• H+ and OH- are very reactive and can drastically affect the chemistry of the cell

• The concentration of H+ and OH- affects the pH of a solution

Acids and Bases

• The pH scale measures how acidic or basic a solution is

• Acids are numbers below 7 on the pH scale

• Bases are numbers above 7 on the pH scale

Acids are substance that increases the hydrogen ion concentration of a solution

• The more H+ in a solution, the more acidic it is

• When HCl (hydrochloric acid) is added to a solution, hydrogen ions dissociate from chlorine ions, adding H+ to the solution

  • HCl + H+ → Cl-

Bases substance that reduces the hydrogen ion concentration of a solution is a base

• The less H+ in a solution, the more basic it is

• Some bases directly reduce the H+ concentration by accepting hydrogen ions

• NH3 + H+ ←→ NH4+

Organisms and pH

• Human blood is pH 7.4, if it changes the person will die

• Cells use buffers to keep their pH levels within a comfortable range

Temperature Moderation

• Atoms and molecules have kinetic energy due to the fact that they’re always moving

• Heat the measure of the total kinetic energy due to molecular motion in a body of matter

• Temperature the intensity of heat in a body of matter due to the average kinetic energy of molecules

• When two objects of different temperatures come together, heat passes from the warmer object to the cooler object until they’re the same temperature

Unit 1 - Organic Molecules ✓

https://docs.google.com/presentation/d/13LxD5zBm_mS5Qh6AlSzOYfsVi3uBHVcZ7S8M0KPSaI8/edit#slide=id.p1

Macromolecules are composed of small organic molecules

• Make up all living things

• 4 main classes

  • Carbohydrates

  • Lipids

  • Proteins

  • Nucleic acids

Polymers and Monomers

• Polymer is a long molecule composed of many similar building blocks linked by covalent bonds

  • Poly = many

• Monomers are the small building blocks that compose polymers

  • Mono = one

Making and Breaking Polymers

• All cells use similar processes to assemble and break apart macromolecules

• These processes are facilitated by enzyme

• Dehydration reactions build polymers

• Hydrolysis breaks polymers

Dehydration Reaction links monomers together to form polymers

• Both monomers contribute part of a water molecule

  • One monomer contributes an OH group

  • The other contributes an OH

• Product = water

Hydrolysis breaks apart polymers

• Bonds are broken apart by the addition of water molecules

• A hydrogen attaches one monomer and an OH attaches to the other monomer

• Utilized by the body during digestion

Carbohydrates

• Include sugars and their polymers

• Monosaccharides are the simplest carbohydrates

• Disaccharides are composed of two monosaccharides

• Polysaccharides are polymers of many monosaccharides

Monosaccharides are the monomers for carbohydrates

• Their molecular formulas are typically C_nH_2nO_n

  • Glucose is C₆H₁₂O₆

• Most sugar names end in –ose

• Monosaccharides are classified by the
  number of carbons in their carbon skeleton

  • Carbon skeletons range from 3-7 carbons long

  • 6-carbon sugars like glucose are hexoses

• Most sugars form rings when in an aqueous solution

• Monosaccharides are used as a major source of nutrients for cellular work

Glycosidic Linkage

• Two monomers can join together with a glycosidic linkage to form a disaccharide

  • A disaccharide is two monomers linked together

• Maltose is formed by joining two glucose molecules

• Sucrose is formed by joining fructose and glucose

• Lactose is formed by joining glucose and galactose

Polysaccharides are composed of hundreds of monosaccharides

• Some are used as energy reserve

• Others are used as building materials

Starch is a storage polysaccharide used by plants

• Composed entirely of glucose monomers

• Plants store glucose as starch and draw upon it as needed for energy

Glycogen animals store glucose in a polysaccharide

• Glycogen is a highly branched molecule

• Vertebrates store glycogen in the liver and muscles and break it down to release glucose

Cellulose is a polysaccharides that helps to make up cell walls in plants

• Humans can’t digest

• Many eukaryotic herbivores have a symbiotic relationship with cellulose digesting microbes

Polysaccharides Shapes

• Differences in glycosidic linkages contribute to different shapes in polysaccharides

• A β glucose is one that is above the plane of the ring

• An α glucose is one that below the plane of the ring

• Differences in the positioning of glucoses in polysaccharides affects the shape of the polysaccharide

Alpha and Beta Linkages

• Starch is composed mainly of alpha linkages

  • This gives starch a more helical shape and allows it to be branched

  • Ex) Glycogen

• Cellulose is made up of beta linkages

  • This gives cellulose a more linear shape

  • Because of this, cellulose strands are able to bond with adjacent strands, strengthening the fibers

  • Humans can’t  digest these beta linkages

Chitin is a structural polysaccharide

• Found in exoskeletons of arthropods and in the cell walls of fungi

• Similar to cellulose

• Chitin has β linkages

Lipids are often referred to as fats or waxes

• Have little or no affinity for water because they are nonpolar

• Useful both as a long-term energy source and structurally

Fats store large amounts of energy

• Composed of glycerol and fatty acids

• Glycerol is a 3 carbon alcohol

• A fatty acid consists of a carboxyl group attached to a long carbon skeleton

Triglycerides (triglycerol) is composed of a glycerol bound to 3 fatty acids

• Fatty acids can be the same or different

• Fatty acids are joined to the glycerol by dehydration synthesis

Saturated Fatty Acids if there are no carbon-carbon double bonds in the fatty acid

• It’s saturated with hydrogens in every possible position

• Solid at room temperature and can lead to cardiovascular diseases

Unsaturated Fatty Acids have one or more double bonds in the carbon skeleton

• Have a kink in the carbon skeleton

• These fats are liquid at room temperature and aren’t as unhealthy

Fat Energy Storage to store energy

• A gram of fat stores more than twice the amount of energy as a gram of carbohydrate

• Plants use fat storage in the form of oils in seeds

• Humans and other mammals store fats as long term energy reserves in adipose cells

Phospholipids is composed of a glycerol attached to a phosphate and two fatty acids

• Cell membranes are made largely of phospholipids

• The phosphate head of the phospholipid is hydrophilic

• The fatty acid tails of the phospholipid are hydrophobic

Phospholipids arrange themselves as a bilayer when exposed to water

• The tails of one each side of the layer point in to avoid the water

• The heads of the phospholipids point out towards the water

• This forms the main component of cell membranes

Steroids are lipids with a carbon skeleton composed of four fused rings

• Cholesterol is a steroid found in animal cell membranes

  • High levels of cholesterol can  contribute to cardiovascular disease

• Testosterone and estrogen hormones are steroids

Proteins

• Functions including:

  • Structural support

  • Storage

  • Transport

  • Defense

  • Movement

• Protein enzymes function as catalysts in cells

• Polypeptides make up proteins

• Amino acids make up polypeptides

Amino Acids are the monomers of proteins (they contain both carboxyl and amino groups)

• The amino acid is composed of 4 things attached to a central carbon atom:

  • A hydrogen atom

  • A carboxyl group

  • An amino group

  • A variable R group

R Group determines the characteristic of the amino acid

• Each 20 amino acid has its own R group

• R groups can be:

  • Polar

  • Nonpolar

  • Negatively Charged

  • Positively Charged

Joining Amino Acids together by dehydration synthesis

• The covalent bond that links amino acids together is called a peptide bond

• When many amino acids are linked together, they form a polypeptide chain

  • The N-terminus of the chain has a free amino group

  • The C-terminus of the chain has a free carboxyl group

Protein Formation

• A protein consists of one or more polypeptides arranged into a unique shape

• The order of amino acids determines the shape of the protein

• The shape of the protein spontaneously forms due to the interactions of the polypeptide chain with itself

• Different amino acids on the chain bind to one another, reinforcing the shape of the chain

• The shape of the protein determines its function

Primary Structure protein is its unique sequence of amino acids

• This is just the amino acids that make up the polypeptide chain and the order in which they’re found

• A slight change in primary structure can have large repercussions

Secondary Structure the coils and folds in the polypeptide chain that give the chain shape

• Weak hydrogen bonds between many amino acids in the chain hold the secondary structure together

  • Each hydrogen bond is weak individually, but together, they’re strong

α helix is a secondary structure in which the polypeptide chain coils

• Hydrogen bonds between every 4^th amino acid hold the structure together

β pleated sheet is a secondary structure

• In a pleated sheet, multiple regions of the chain lying side by side are connected by hydrogen bonds between parts of the two parallel polypeptide backbones

Tertiary Structure is the 3D shape of the entire protein

• Determined by interactions among various R groups including:

  • Hydrophobic interactions

  • van der Waals interactions

  • Ionic bonds

  • Hydrogen bonds

Disulfide Bridges

• Strong covalent bonds between sulfhydryl groups of cysteine amino acids help to hold the 3D shape of the protein

• These bonds are called disulfide bridges because two sulfides connect to one another

Quaternary Structure results from the aggregation of two or more polypeptides

• This is when a protein is made of multiple polypeptides

• Hemoglobin is a protein with a quaternary structure

  • It’s composed of 4 different
    polypeptides

Denaturation

• Protein structure depends on the physical and chemical conditions of the protein’s environment

• Alterations in pH, salt concentration, or other factors can denature a protein by disrupting bonds that hold it together

• When a protein is denatured , its shape is changed and it can’t function as normal

• Denatured proteins are biologically inactive

Chaperonins help unfold proteins

• Protect the polypeptide while it’s folding

• Misfolded proteins can be fixed by the chaperonins 

  • Misfolded proteins can lead to diseases such as Alzheimer's, Parkinson’s, and mad cow disease 

Nucleic Acids

Genes

• The amino acid sequence of a polypeptide is decoded by a gene

• A gene is composed of DNA

• Nucleic acids include DNA and RNA

• Nucleic acids are made up of monomers called nucleotides

RNA and DNA

• DNA encodes for proteins that make up the body

  • Found in the nucleus

• RNA takes the information from DNA and uses it to make proteins

  • Messenger RNA is made by reading DNA and encodes for proteins

• Protein synthesis occurs on ribosomes

Nucleotides

• Nucleic acids are polymers that are made up of nucleotides

• Each nucleotide is composed of 3 parts:

  • A nitrogenous base

    • A, T, C, G, or U

  • A pentose sugar

  • A phosphate group

Pyrimindes and Purines

• Nitrogenous bases can be classified as purines or pyrimidines 

• Pyrimidines have single six-membered rings composed of carbon and nitrogen

  • Cytosine (C), Thymine (T), and Uracil (U)

• Purines have a six-membered ring
  joined to a five-membered ring

  • Adenine (A) and Guanine (G)

Nucleotide Pentose

• The pentose in RNA is ribose

• The pentose in DNA is deoxyribose

  • The only difference between the two is that deoxyribose lacks an oxygen atom on carbon 2

Polynucleotides are created when nucleotides are joined by covalent bonds

• The bonds that join nucleotides are called phosphodiester bonds

• The OH group on the 3’ end of one nucleotide links to the phosphate on the 5’ end of the other

DNA Double Helix (shape of DNA)

• The sugar-phosphate backbones of the two polynucleotides are on the outside of the helix

• The backbones run in opposite 5’ —> 3’ directions

  • Their arrangement is said to be antiparallel 

• The strands are held together by hydrogen bonds between the paired bases

• Adenine pairs with thymine

  • 2 hydrogen bonds between the two

• Guanine pairs with cytosine

  • 3 hydrogen bonds between the two

• The two strands are complementary
  to one another

DNA Replication each strand acts as a template to order nucleotides in a new complementary strand

• This ensures that the correct set of genetic information is transmitted when a cell reproduces

RNA

• Complementary pairing is also important in RNA

• Transfer RNA delivers its amino acids based on base pairing

• In RNA, there is uracil instead of thymine

  • It pairs with adenine

• RNA is typically single-stranded

Unit 2 - Cells

https://docs.google.com/presentation/d/1zkrfYmZHKU_6nKkKX7z3zw5-TKmEu7AzexH9UCnO2GE/edit#slide=id.p1

Cells

• All organisms are made of cells

• The cell is the simplest collection of matter that can be alive

• Cells are the basic building block of life

Microscopy

• The development of microscopes allowed for the discovery of cells

• In light microscopes, visible light passes through the specimen and through the glass lenses

  • These can distinguish between individual cells, but can’t see the organelles

• In electron microscopes, a beam of electrons passes through the specimen 

  • These can see smaller things such as organelles

Electron Microscopy

• Scanning electron microscopes (SEMs) are used for studying the surface structure of a specimen 

  • The image seems three-dimensional

• Transmission electron microscopes (TEMs) are used to study the internal structure of cells

• Magnification – the ratio of an object’s image to real size

  • A light microscope can magnify to about 1000x

• Resolution – a measure of image clarity

• Contrast – accentuates differences in parts of the sample 

  • The higher the contrast, the easier it is to tell the two things apart

Cell fractionation is a technique that takes cells apart and separates major organelles and other subcellular structures

• A centrifuge spins test tubes with mixtures of disrupted cells

• Different organelles settle into pellets at the bottom of the test tube at different speeds

PROKARYOTIC VS. EUKARYOTIC CELLS

• Bacteria and Archaea have prokaryotic cells

  • Prokaryotic cells are between .1µm and 5 µm 

• Protists, fungi, animals, and plants have eukaryotic cells

  • Eukaryotic cells are between 10 and 100 µm 

• Eukaryotes house their DNA in a membrane-bound nucleus

  • Prokaryotes don’t have a
    nucleus, they have a
    nucleoid region

• Eukaryotic cells have membrane-bound organelles, while prokaryotes
  don’t

Unit 2 - Cells Transport

https://docs.google.com/presentation/d/1fFcBwFSwcY4VL2suQwtU6JtpkgKfr7a-q5lWrWVjWww/edit#slide=id.p1

Unit 3 - Enzymes

https://docs.google.com/presentation/d/1GpAmcUCyzF8BzLc1DAr2Qw7q9KbnuBiNgO7r3MRmg7k/edit#slide=id.p1

Unit 3 - Photosynthesis

https://docs.google.com/presentation/d/1BIO8OlZm525FPklZ0-gGzn2s12N7hV0NYYrnU2_hHvU/edit

Unit 3 - Cellular Respiration

https://docs.google.com/presentation/d/1SncHcomeGN95F8DZ3cFShIfnuHiEpkjE3bI98fMH48M/edit

Unit 4 - Cell Communication

https://docs.google.com/presentation/d/1-JPeM7LN0OrR2VtqX7AwDMx3-PtFXKxEKktzlAy5vjQ/edit#slide=id.p14

Unit 4 - Cell Cycle

https://docs.google.com/presentation/d/1Yaox5vSTWaESgRChLJ8_obmjPq1Shmen00OldD1Fumo/edit#slide=id.p1

Unit 5 - Meiosis

https://docs.google.com/presentation/d/1pxKHZtOqSLNL_lcUg6fsHvaN7VGDq93g0E_IhK9waH0/edit#slide=id.p1

Unit 5 - Genetics

https://docs.google.com/presentation/d/1J2YSDfG8vxATLm31XWnyWWzOZp0nF12Q5lPUNwGaeJ0/edit

Unit 6 - DNA

https://docs.google.com/presentation/d/1CfKKUX2rLSbYSQ5TjF6Duf9xjnT6rai-gyjMYaDV7jI/edit#slide=id.p1

Unit 6 - Protein Synthesis

https://docs.google.com/presentation/d/1blA4Wq_4YsMshR7qqf8x7RpXOgl9-vxS9kroY-kCXvg/edit

Unit 7 - Natural Selection ✓

Hardy Weinberg

https://docs.google.com/presentation/d/1yiO-cSxfEeuPM1MkRQkmWrB3M21pEx2S5d_chevbHZY/edit#slide=id.g1107acb59d5_0_187

Hardy Weinberg Equilibrium describes a non-evolving population

• It states that the frequencies of all alleles and genotypes in the population in the population

Equation

• p + q = 1

  • p = frequency of the dominant allele

  • q = frequency of the recessive allele

• p² + 2pq + q² = 1

  • p² = frequency of homozygous dominant genotype

  • 2pq = frequency of heterozygous genotype

  • q² = frequency of homozygous recessive genotype

Hardy-Weinberg has 5 assumptions

• For a population to remain in Hardy-Weinberg equilibrium, the genes of the population must be unchanging

1. Very large population size

   • In small populations, chance fluctuations in the gene pool will cause allele frequencies to change over time

2. No migration

   • For the frequency of genes to remain the same, there must be no new genes entering the population via immigration and none leaving via emigration

3. No net mutations

   • The gene pool is modified if mutations occur

4. Random mating

   • If non-random mating occurs, some traits will be passed on with greater frequency than others

5. No natural selection

   • If natural selection occurs, favorable genes will be passed on with greater frequency

Assumptions of Hardy-Weinberg

• Whenever a population is violating a tenant of Hardy-Weinberg, it’s evolving

• Does not occur in nature

Speciation and Trees

https://docs.google.com/presentation/d/1CtRC3gzqZGYNaWf3mCEwexVQahBWXzTeY9LU1E2xWRo/edit#slide=id.p1

Speciation the process by which one species splits into two or more species

• Bridges the gap between microevolution and macroevolution

Biological species concept defines a species as a group of populations that have the potential to interbreed in nature and produce viable, fertile offspring

• Different species are separated by reproductive isolation

  • Reproductive isolation is the existence of biological barriers that prevent members of two species from producing viable, fertile offspring

Prezygotic and Postzygotic Barriers

• Prezygotic barriers block fertilization between species

  • A zygote never forms

  • Either mating doesn’t occur, or something hinders fertilization

• Postzygotic barriers prevent the hybrid zygote from developing into a viable, fertile adult

Prezygotic Examples

• Habitat Isolation two organisms that use different habitats are unlikely to encounter each other to even attempt mating

• Behavioral Isolation species use unique and elaborate courtship behaviors to attract mates

• Temporal Isolation two species that breed during different times of day, different seasons, or different years cannot mix gametes

  • Ex: The western skunk mates in the summer and the eastern skunk mates in the winter

• Mechanical Isolation closely related species may attempt to mate, but fail because they are anatomically incompatible and the transfer of sperm isn’t possible

  • Snails whole shells coil in opposite spirals and cannot mate with each other

• Gametic Isolation some of the gametes of two species do not form a zygote because of incompatibilities preventing fertilization

  • The female reproductive tract may be incompatible, the sperm and egg may not recognize each other, etc.

Postzygotic Barriers

• Reduced Hybrid Viability genetic incompatibility between the two species may abort the development of the hybrid at some embryonic stage or produce frail offspring

  • Occasional hybrids form by salamanders that belong to the same genus

• Reduced Hybrid Feritlity even if the hydrib offspring are vigorous, they’re infertile

  • When a donkey and a horse mate, they produce a mule

• Hybrid Breakdown first-generation hybrids are viable and fertile, but the next generation is feeble or sterile

  • Some strains of rice have viable hybrids, but the next generation of hybrids are small and sterile (speciation)

• Reproductive Barriers keep different species separate from each other

  • If two populations can’t interbeed, they’ll start to diverge into different species

Alternative Species Concepts

• Limitations of the Biological Species Concept

  • Can’t test for extinct organisms (cuz they r dead <3)

  • Can’t test for organisms that reproduce asexually

• Ecological Species Concept defines a species in terms of its ecological niche

  • Cosiders the sum of how members of the species interact with the nonliving and living parts of their environment

  • Can accommodate asexual and sexual species

• Phylogenetic Species Concept defines species based one a shared common ancestor (the stupid tree <3)

  • A single branch in the tree of life is a species

  • Morphology and molecular sequences of species are analyzed to determine the evolutionary history of a species

Modes of Speciation

• Allopatric Speciation geographic separation of populations restrict gene flow

  • A population is fragmated by a geographical feature into two or more isolated populations

  • Because the two populations are reproductively isolated, they diverge evolutionarily

Sympatric Speciation speciation occurs in populations that live in the same geographic area

• Occurs by:

  • Polyploidy

  • Natural Selection

  • Sexual Selection

  • Artificial Selection

Polyploidy

• Sympatric speciation can result from accidents in cell division that result in extra sets of chromosomes

• Most common in plants (bc it can self-fertilize, easier to create new species)

Natural Selection

• Diversifying selection can lead to sympatric speciation

• If both extremes are selected for in a population, it can cause it break into two new species

Sexual Selection mates are chosen based on physical appearance

• Can also lead to sympatric speciation

Tempos of Speciation

• Gradualism a species changes slowly over time

  • It’s difficult to determine when a new species arises, as the change is slow (takes many generations)

• Punctuated Equilibrium there are long periods of stasis followed by periods of rapid change

  • Suppose that a species survived for 5 million years, but most of its morphological alterations occurred in the first 50,000 years of its existence—just 1% of its total lifetime (still takes a long time, but it’s quicker)

Patterns of Evolution

• Divergent Evolution occurs when a population becomes isolated from the rest of the species, becomes exposed to new selective pressures, and evolves into a new species

  • How new species arise

  • A new species diverges from the original species

• Convergent Evolution occurs when unrelated species occupy the same environment, are subjected to similar pressures, and evolve in similar ways

  • The two unrelated organisms start to resemble each other and show similar adaptations

  • Analogous Structures are structures that have similar functions, but different evolutionary histores (ex. wings in butterflies and birds)

• Parallel Evolution two species make similar evolutionary adaptations after divergence from a common ancestry

• Coevolution two species who interact evolve together

  

Phylogenetic

Dear King Philip Came Over For Good Soup

• Dear → Domain

• King → Kingdom

• Philip → Phylum

• Came → Class

• Over → Order

• For → Family

• Good → Genus

• Soup → Species

Skin Color

Darker skin (eumelanin) = more melanin, less Vitamin D, and more folate

Light Skin (pheomelanin) = less melanin, more Vitamin D, and less folate

Brown skin (eumelanin) = mid

Unit 8 - Ecology

Animal Behavior

https://docs.google.com/presentation/d/1E270nqgwD5IppIcbpq3kHZvaQpq4y2dasZK2liVLMTk/edit#slide=id.p1

Behavior is an action carried out by the muscles under control of the nervous system in response to the stimulus

• Allows an animal to respond to its environment

  • Survival

  • Reprodcution

• It’s subjective to natural selection

  • Those with beneficial behaviors survive better and pass those behaviors on to offspring

Types of Behavior

• Innate Behaviors that are present at birth – nearly all individuals in a population exhibit this behavior

• Learned Behavior that is modified based on experience

Fixed Action Patterns is the behavior in which a sequence of unlearned acts is directly linked to a specific stimulus (aka reflexes on steroids)

Migration is an example of animals responding to an environmental stimulus

• It is a regular, long-distance change in location

• Animals are guided by the position of the sun, Earth’s magnetic field and their evolved ancestral behaviors in order to reach a particular destination

Foraging Behaviors are influenced by natural selection

• This includes: obtaining and eating food

• The optimal foraging model states that natural selection should favor a foraging behavior that minimizes the costs of foraging while maximizing the benefits

• The optimal time is defined

Mating Behaviors and Choices

• The needs of the young are important for the evolution of mating systems

• Species that are young require more care and tend to be monogamous

• Species whose young require less care tend to be promiscuous

Certainty of Paternity Males who know that they are the father will protect their offspring, but if they are uncertain then they won’t be as involved

Animal Communication a stimulus is transmitted from one animal to another is called a signal

• Transmission and reception of signals constitute animal communication

• Communication allows animals to interact with each other

Methods:

• Visual - through sight

• Tactical

• Electrical

• Chemical

Bees are able to communicate with one another where food sources are by dancing

• Based on dance moves the bees perform for their bee buds, the other members of the hives are able to find where te food is

• Allows the needs to respond to their environment

Pheromones animals that communicate through odors or tastes emit a chemical substance

• It can be used for:

  • Find mates

  • Dissuade predators

  • Establish dominance

  • Serve as alarm signals to warn others of danger

Genetic Basis of Behavior

• Certain individual genes can have a profound impact on behavior

• A single gene can have a profound impact on behavior

• Ex: Prairie vole

Prairie Vole Love

• Male meadow voles are solitary and do not form lasting relationships with mates

• Male prairie voles form a pair bond with a single female after they mate, taking care of their offspring

• Male prairie voles release a neurotransmitter known as vasopressin during mating

• If prairie voles are treated with a drug that inhibits the vasopressin receptor, they don’t form pair bonds after mating

• When the vasopressin receptor gene is inserted into the meadow voles, they take care of their young

Altruism describes behavior that reduces an individual’s fitness but increases the fitness of other individuals in the populations

• Allows for the success of the whole, which ends up helping the individual

• Having a strong community = safety + security for all members

• This occurs in families, as the members of the family have a lot of common DNA

Energy Flow

https://docs.google.com/presentation/d/1MtSXJt8Etf8k_gGL7y5N0YcgxMDY_EPYNhuKiE9yauE/edit#slide=id.p1