Unit 1 - Unit 8 AP Biology Comprehensive Review

Flashcards covering AP Biology concepts from Biochemistry and Cell Structure to Evolution and Ecology, Ecology formatted as vocabulary terms based on lecture transcripts.

Polarity of Water

A property resulting from the uneven sharing of electrons between oxygen and hydrogen, where oxygen is slightly more negative and hydrogen is slightly more positive, leading to the formation of polar covalent bonds.

Specific Heat Capacity

The amount of energy required to heat water up, which is high because hydrogen bonds are hard to pull apart and molecules must move faster to increase temperature.

Cohesion

The property of water molecules sticking together due to their polarity and mutual attraction.

Adhesion

The property of water molecules sticking to other polar surfaces.

Capillary Action

The movement of water up narrow tubes, such as the xylem in vascular plants, driven by cohesion and adhesion.

Surface Tension

A property created by cohesion and strong hydrogen bonds that makes the surface of water difficult to break through.

Organic Molecules

Molecules that originate from living things and contain carbon atoms bonded to one another.

Macromolecules

The four most important biological molecules in living systems: Carbohydrates, Proteins, Lipids, and Nucleic Acids.

Hydrolysis

A biological reaction that breaks down large molecules into smaller ones by adding water, attaching a hydrogen ion $-H$ to one monomer and a hydroxyl $-OH$ group to the other.

Dehydration Synthesis

A reaction where two smaller molecules are joined by covalent bonds through the removal of water ($-H$ from one and $-OH$ from another).

Monosaccharides

The monomers of carbohydrates, also known as simple sugars, such as glucose and fructose.

Polysaccharides

Complex carbohydrates formed from linked monosaccharides, used for fuel or structure; examples include cellulose, starch, and glycogen.

Saturated Fatty Acid

A lipid monomer with only single bonds between carbon atoms, resulting in a straight hydrocarbon chain.

Unsaturated Fatty Acid

A lipid monomer containing at least one double bond between carbon atoms, creating a kink or bend in the chain.

Phospholipid

A lipid made of fatty acids and a phosphate group that arranges into a bilayer to create cell membranes.

Nucleotide

The monomer of nucleic acids, consisting of a phosphate group ($PO_4$), a 5-carbon sugar (ribose or deoxyribose), and a nitrogenous base.

Antiparallel

The structural arrangement of DNA where the two strands run in opposite directions ($5' \rightarrow 3'$ and $3' \rightarrow 5'$).

Amino Acid

The monomer of proteins, consisting of an amine group ($NH_2$), a carboxyl group ($COOH$), a central carbon, and a variable R-group.

Polypeptide

A polymer consisting of many amino acids linked together by covalent peptide bonds formed through dehydration synthesis.

Primary Structure

The first level of protein structure, consisting of the linear sequence of amino acid monomers.

Secondary Structure

The level of protein structure where hydrogen bonds between the backbone form alpha helices or beta-pleated sheets.

Tertiary Structure

The three-dimensional shape of a protein determined by R-group interactions, including hydrophobic interactions, disulfide bridges, and ionic bonds.

Quaternary Structure

The level of protein structure determined by the interactions between multiple polypeptide subunits.

Ribosomes

Organelles made of rRNA and proteins that synthesize proteins based on mRNA sequences.

Rough Endoplasmic Reticulum

A system of membranes embedded with ribosomes that makes proteins and helps maintain cell shape.

Smooth Endoplasmic Reticulum

A system of membranes that detoxifies the cell and synthesizes lipids.

Golgi Apparatus

Flat membrane sacs that modify, package, and ship cellular products, especially proteins and lipids from the ER.

Lysosome

A membrane-enclosed sac containing hydrolytic enzymes used to break down materials and aid in apoptosis.

Turgor Pressure

The pressure exerted by water against the plant cell wall when the large central vacuole fills up.

Mitochondria

The site of cellular respiration in eukaryotes, featuring a double membrane with a folded inner membrane (cristae) to produce ATP.

Chloroplast

A double-membrane organelle in plants and algae where photosynthesis occurs, containing stacks called granum and discs called thylakoids.

SA:V Ratio

The Surface Area to Volume ratio; a higher ratio allows for more efficient exchange with the environment.

Amphipathic

A molecule having both polar and nonpolar regions, such as a phospholipid.

Active Transport

The movement of substances from low to high concentration across a membrane, requiring cellular energy in the form of ATP.

Facilitated Diffusion

A form of passive transport that requires a channel protein to move molecules through the cell membrane.

Hypertonic

A solution with a higher solute concentration compared to the inside of the cell, causing water to leave the cell.

Hypotonic

A solution with a lower solute concentration compared to the inside of the cell, causing water to enter and swell the cell.

Water Potential ($\Psi$)

The sum of pressure potential ($\Psi_p$) and solute potential ($\Psi_s$), representing the potential energy of water; water flows from high potential to low potential.

Solute Potential Formula

$\Psi_s = -iCRT$, where $i$ is the ionization constant, $C$ is molar concentration, $R$ is the pressure constant ($0.0831 \, L \, bars/mole \, K$), and $T$ is temperature in Kelvin.

Enzyme

A protein acting as a biological catalyst that speeds up reactions by lowering the activation energy.

Active Site

The specific region on an enzyme where substrates bind for catalysis based on shape and charge compatibility.

Denaturation

The unfolding of a protein (like an enzyme) due to external conditions like high temperature or extreme pH, causing a loss of function.

Competitive Inhibitor

A molecule that binds to the active site of an enzyme, blocking the substrate from binding.

Allosteric Inhibitor

A non-competitive inhibitor that binds to a site other than the active site, deforming the enzyme so the substrate cannot fit.

Metabolic Pathway

A sequence of chemical reactions where the product of one reaction serves as the reactant for the next to conserve energy.

Energy Coupling

The process of pairing an exergonic reaction (releases energy) with an endergonic reaction (requires energy) to reduce energy loss.

Light Reactions

Metabolic pathways in the thylakoid membrane that capture light energy to produce ATP and NADPH while releasing $O_2$ as a byproduct.

Calvin Cycle

The series of light-independent reactions in the stroma that fix carbon dioxide into carbohydrates using energy from ATP and NADPH.

ATP Synthase

An enzyme that uses the flow of hydrogen ions ($H^+$) down a concentration gradient to phosphorylate ADP into ATP.

Chemiosmosis

The use of a movement of ions (like $H^+$) from high to low concentration across a semi-permeable membrane to do work, such as producing ATP.

Glycolysis

A metabolic pathway in the cytosol that converts one glucose molecule into two pyruvate, producing a net of $2 \, ATP$ and $2 \, NADH$.

Krebs Cycle

A series of enzyme-mediated reactions in the mitochondrial matrix that produces $6 \, NADH$, $2 \, FADH_2$, and $2 \, ATP$ per glucose molecule.

Fermentation

An anaerobic process that regenerates $NAD^+$ to allow glycolysis to continue producing ATP in the absence of oxygen.

Endocrine Signaling

Long-distance cell communication where signals (hormones) travel through the blood or lymph to target cells.

Ligand

A chemical signal molecule, such as a protein or peptide, that binds to a specific receptor protein to trigger a cellular response.

Kinase

An enzyme that transfers phosphates from ATP to other molecules to activate them and relay a signal.

Second Messenger

Small non-protein molecules, like cyclic AMP (cAMP), that amplify signals and activate multiple transduction pathways.

Apoptosis

A programmed cell death process triggered by cellular signals when a cell is damaged or cancerous.

Negative Feedback

A mechanism that counteracts a stimulus to return a system to its set-point, such as temperature or blood glucose regulation.

Positive Feedback

A mechanism that amplifies a stimulus, moving a system further away from its set-point, such as during fruit ripening or childbirth.

Interphase

The period of the cell cycle where the cell is not dividing, composed of G1 (growth), S (DNA replication), and G2 (preparation for division).

Mitosis

Eukaryotic cell division that transfers a copy of the cell's genome to two genetically identical daughter cells.

Sister Chromatids

Two identical copies of a chromosome connected at the centromere.

Cyclins

Proteins that build up in concentration as the cell cycle proceeds, binding to cyclin-dependent kinases to trigger progression through checkpoints.

Meiosis

A two-stage cell division process that produces four non-identical haploid gametes (sperm or egg cells).

Synapsis

The pairing of homologous chromosomes during Prophase I of meiosis, allowing for crossing over.

Crossing Over

The exchange of genes between homologous chromosomes during Prophase I, resulting in genetic recombination.

Nondisjunction

The incorrect separation of homologous chromosomes or sister chromatids, leading to aneuploidy (wrong number of chromosomes).

Codominance

A pattern of inheritance where both alleles are dominant and expressed in the phenotype, such as Type AB blood.

Incomplete Dominance

A pattern of inheritance where neither allele is fully dominant, resulting in a blended phenotype in heterozygotes (e.g., pink flowers from red and white parents).

Linked Genes

Genes located on the same chromosome that are more likely to be inherited together, showing less than $50\%$ recombination frequency.

Phenotypic Plasticity

The ability of one genotype to produce different phenotypes in response to different environmental conditions.

Helicase

The enzyme responsible for separating the two template strands of DNA during replication.

Semiconservative Replication

DNA replication where each new DNA molecule consists of one original template strand and one newly synthesized strand.

Alternative Splicing

The process by which different sections of a single pre-mRNA transcript are treated as introns or exons, resulting in different mature mR-NAs.

Retrovirus

A type of virus that uses reverse transcriptase to convert its RNA genome into DNA and integrate it into a host cell's genome.

Operon

A group of coordinately controlled genes in prokaryotes that are usually expressed together; examples include the lac and trp operons.

Genetic Drift

A random change in allele frequencies, most impactful in small populations, often occurring through the bottleneck or founder effects.

Hardy-Weinberg Equilibrium

A model predicting that allele frequencies remain constant in a non-evolving population, calculated using $p^2+2pq+q^2=1$.

Allopatric Speciation

The formation of new species due to the physical separation of populations by geographic isolation.

Sympatric Speciation

Speciation occurring within the same geographic area due to isolation types other than physical barriers.

RNA World Hypothesis

The theory that self-replicating RNA was the first genetic material and catalyst for life, preceding DNA and proteins.

Keystone Species

A species that has a disproportionately large effect on its ecosystem relative to its abundance.

Simpson's Diversity Index ($Ds$)

A measure of healthy community structure calculated by $1 - \sum(n/N)^2$, where high values represent higher resilience to change.

Biomagnification

The accumulation of toxins in higher concentrations in animals at higher trophic levels.

Eutrophication

The process where excess nutrients from runoff cause excessive algae growth, depleting oxygen in aquatic ecosystems.

Carrying Capacity ($K$)

The maximum number of individuals in a population that an environment's resources can sustainably support.

Logistic Growth

An S-curve population growth pattern that slows as the population size reaches the carrying capacity ($K$).