ap bio semester 2

A set of flashcards to help review key vocabulary terms and concepts from biology lecture notes.

Fixed Action Pattern (FAP)

Unlearned acts directly linked to a simple stimulus, usually occurring in a series of actions the same way every time and triggered by a sign stimulus.

Innate Behaviors

Behaviors that are instinctual, due to genetic programming without environmental influence.

Learning

A change in behavior resulting from experience.

Habituation

Decreased response to a repeated stimulus because it is a meaningless stimulus.

Imprinting

Learning that involves both innate behavior and experience and is limited to a sensitive period in an animal’s life.

Sensitive (Critical) Period

Limited phase in an animal’s development when learning of a particular behavior can take place.

Associative Learning

Associating one stimulus or response with another stimulus, often involving reward/punishment.

Excitatory

More positive inside, making it more likely to fire.

Inhibitory

Postsynaptic cell more negative, making it harder to fire.

EPSP

Excitatory postsynaptic potential.

IPSP

Inhibitory postsynaptic potential.

Mechanoreceptors

Pressure, touch, stretch, motion, sound.

Chemoreceptors

Relay information about total solute concentration or individual kinds of molecules.

Thermoreceptors

Heat and cold.

Nociceptors

Pain.

Photoreceptors

Light.

Ganglia

Clusters of neurons.

Neurotransmitter

Chemical message.

Presynaptic

Before the synapse.

Postsynaptic

After the synapse.

Myelin

Packets of fat that surround the axon of a neuron.

Sodium-Potassium Pump

Active transport, 3 sodium out, 2 potassium in.

Rest Potential

Relatively positive outside.

Action Potential (Depolarization)

Facilitated diffusion where inside becomes positive.

Repolarization

Potassium moves out, so outside becomes positive.

Acetylcholine

Excitatory and inhibitory neurotransmitter.

Dopamine

Excitatory neurotransmitter; lack causes Parkinson's, excess causes schizophrenia.

Serotonin

Inhibitory neurotransmitter.

Endorphins

Inhibitory neurotransmitter; body’s natural painkiller.

Kinetochore

Centrioles form microtubule spindle; what joins chromosomes.

Telophase; Cytokinesis

Nucleus splits; cell splits.

TATA Box

Starts transcription.

Signaling Molecules

Hormones are secreted into surrounding fluid (endocrine system).

Paracrine; Autocrine

Neighboring cells; self signaling.

Pheromones

Act as mate attractant, territorial markers, or alarm.

Steroid Hormones

Lipid molecules from cholesterol, includes sex hormones.

Amino Acid Hormones

Amine, peptide, protein glycoproteins; unable to pass plasma membrane so uses STP (signal transduction pathway).

Statoliths

Dense starch grains that fall to low points of cells, causing redistribution of auxins.

Thigmotrophism

Directional growth in response to touch.

Nervous System

Electrical message via ions/neurotransmitters; rapid, short-lived communications along dedicated routes of nerves (axons) lasting only faction of a second; responsible for reflexes and rapid movement.

Endocrine System

Chemical message with hormones; slow, long-lasting communications to all locations since hormones remain in blood for minutes/hours; response for gradual changes such as growth, development, reproduction, metabolic process, digestion.

Positive Feedback Loop

Feedback → effect amplified.

Auxin

Auxin is the growth hormone in plants that responds to light.

Auxins and Cytokinins

Growth hormones; auxin producted at tip and base at plant to grow vertically.

Cytokinins

Causes lateral growth.

Giberrelins

Causes fruit to grow big.

ABA: Abscisic Acid

Promotes dormancy.

Ethylene

Hormone (gas) that ripening fruit produce.

Phototropism

Tree knows to grow towards light.

Gravitrophism

Tree knows to grow up/down vertically.

Homeotic Genes

Determine basic features, such as where wings and legs will develop on a bird, and how a flower’s parts are arranged.

Hox Genes

Provide positional information during development.

Heterochrony

Evolutionary change in the rate/timing of developmental events.

Exaptation

Structures that evolve in one context but become co-opted for a different function.

Cell Signaling

Cell-cell communications are essential for multicellular organisms, an organism develops from a fertilized egg, involving cell differentiation, function, reproduction.

Apoptosis

Programmed cell death.

Synaptic Signaling

Nerves; allows for quick reflexes.

Paracrine Signaling

This is seen in histamines (allergy, mosquito bites, etc). Histamines released by cells cause the allergic reaction.

Long-Distance Signaling

Plants and animals use chemicals called hormones; seen in testosterone.

Ligand

Signaling molecule.

G-Protein Coupled Receptor (GPCR)

G-protein activated by signaling molecule; ligand changes the shape of the receptor protein → GTP want to interact with something since they are electronegative → g-protein activated.

Ligand-Gated Ion Channel

Outside message ligand binds the protein; the flap of the protein receptor normally prevents ions from going in; later, ligand binding → protein shape change → ions can enter → cellular response.

Intracellular Receptors

The cells have certain receptors. those with the receptors have the cellular response; testosterone is able to pass through the membrane because it is hydrophobic (even if it is larger).

CAMP as the Second Messenger

Adenylyl cyclase attracts ATP and cAMP is left; this promotes a protein kinase-like protein kinase A to have a cellular response; acts as the volume control.

Protein Phosphorylation and Dephosphorylation

Protein kinases transfer phosphates from ATP to protein, a process called phosphorylation; protein phosphatases remove the phosphates from proteins, a process called dephosphorylation; acts as a molecular switch, turning activities on and off.

Particles Moving Through Membrane

Small, uncharged particles have easier time moving through membrane; otherwise they need facilitated diffusion via carrier proteins (passive transport from high → low concentration).

Water Potential

More concentrated something is, more negative water potential is.

Competitive Inhibitors

Directly completes with active site.

Noncompetitive Inhibitors

Doesn’t compete w/ active site and is at the allosteric site.

Chemiosmosis

Process of H+ going through ATP synthase and making ATP.

Proton Motive Force

When protons move.

Oxidative Phosphorylation

ETC+ chemiosmosis.

Fermentation

As much cellular respiration as can be done without oxygen; NADH is recycled to keep making atp.

Mass Extinctions

50+% of earth’s organisms die.

Prezygotic Reproductive Barriers

Before fertilization/formation of zygotes.

Habitat Isolation; Behavioral Isolation

Garter snake in water or on land; courtship (songs, pheremones = chemical attractants).

Temporal Isolation

Different breeding time, season, year (cats give birth in April).

Mechanical Isolation

Anatomically can’t get together; same species maybe but physically can’t. Like great Danes cannot mate with Chihuahuas.

Gametic Isolation

Receptor proteins of sperm are too different.

Postzygotic Reproductive Barriers

After fertilization/formation of zygotes.

Reduced Hybrid Viability

Incompatibility causes abortion of embryo; polar bear + grizzlies → pizzlies.

Adaptive Radiation

Evolution of many diversely adapted species from a common ancestor.

Gradualism

Big changes occur due to the accumulation of many small changes over a long time.

Sympatric Speciation

Speciation occurs in populations that live in the same geographic area, can occur if gene flow is reduced by polyploidy (extra sets of chromosomes).

Autopolyploidy; Allopolyploidy

From single species; from two species.

Hybrid Zones

Populations can share genes; over time some barrier → one population isolated → allopatric speciation happened → later hybrid zone → gene flow reestablished.

Macroevolution

Evolution above the species level (photosynthesis, terrestrial vertebrates, mass extinctions, origin of key adaptations).

Fossil Record

In sedimentary rock layers (strata), in amber, in ice; limited because the record has been destroyed by later geologic process and haven’t been discovered yet.

Relative Dating

Scientists have established a geological time scale by studying different stratata at different sites; index fossils at each site can be compared to other sites to show relative age (not years).

Absolute Dating; Radiometric Dating

Fossils contain isotopes that decay at specific rates.

Photosynthesis and Carbon Cycle

Uses rubisco to fix CO2 and goes into stomata (carbon cycle).

Photorespiration

Plants close stomata to conserve water on hot days but then can’t get enough CO2

CAM Plants close stomata by night & C4 use PEP

Temporal Seperation; C4 & CAM Plants

Nitrogen Cycle

Bacteria mostly responsible; fixing nitrogen from air; able to use fixed nitrogen to make plants proteins and also into animals; organisms’ waste strengthens nitrogen cycle.

Phosphorous Cycle

Very electronegative; have lots of potential energy like ATP; also seen in nucleic acids; comes from rocks (minerals erode).

Population

Localized group of individuals belonging to the same species, live in same areas and interbreed.

Species

Group of individuals who can interbreed and produce fertile offspring.

Gene Pool

Consist of all alleles at every locus in all members of a population.

Phylogenic Tree

Arrow = goes to present day; if line ends they’ve went extinct; traits in the branch – all other organisms will have it also.

Claudogram

Sloped line; table with traits (1= has trait; 0 = has no traits); not necessarily related; all inferred relationships (not necessarily common ancestor).