AP Biology Review Flashcards

These flashcards cover the key vocabulary, concepts, and ideas presented in the AP Biology course.

AP Biology

A course designed around four Big Ideas: Evolution, Energetics, Information Storage and Transmission, and Systems Interactions. It has eight units of content.

Null Hypothesis (H0)

States that there is no statistically significant difference between two groups in an experiment.

Chi-Square Test

A statistical test used to compare observed results to expected results in an experiment, often used to evaluate the null hypothesis.

Mean

The average of a data set, calculated by adding all values and dividing by the sample size.

Median

The midpoint of a data set when its members are arranged in numerical order.

Standard Deviation (s)

A measure that averages how far each data point is from the mean of the data set.

Standard Error of the Mean ( )

A measure of how spread out a data set is, predicting the distribution of the means of repeated experiments.

95% Confidence Interval (95% CI)

An interval constructed from the mean and standard error, used to estimate the range within which the true population mean is likely to fall.

Big Idea 1: Evolution

The process of evolution drives the diversity and unity of life.

Big Idea 2: Energetics

Biological systems use energy and molecular building blocks to grow, reproduce, and maintain dynamic homeostasis.

Big Idea 3: Information Storage and Transmission

Living systems store, retrieve, transmit, and respond to information essential to life processes.

Big Idea 4: Systems Interactions

Biological systems interact, and these systems and their interactions exhibit complex properties.

Water

A polar molecule crucial for life, exhibiting cohesive and adhesive behavior, high specific heat, climate moderation, expansion upon freezing, and solvent properties.

pH

The measure of the concentration of H+ ions in a solution; a pH less than 7 is acidic, a pH greater than 7 is basic, and a pH of 7 is neutral.

Carbohydrates

Polymers of sugar monomers used for energy storage and structural functions.

Lipids

Nonpolar macromolecules functioning in energy storage, cell membranes, and insulation.

Nucleic acids

Polymers of nucleotides that are carriers of genetic information (DNA and RNA).

Proteins

Polymers of amino acids that function to catalyze metabolic reactions, maintain structure, and participate in cell signaling.

Primary Structure

The sequence of amino acids in a polypeptide chain.

Secondary Structure

The local folding of polypeptide chains into alpha helices and beta-pleated sheets, stabilized by hydrogen bonds.

Tertiary Structure

The three-dimensional folded shape of a protein, determined by hydrophobic/hydrophilic interactions.

Quaternary Structure

The arrangement of multiple polypeptide subunits in a protein.

Prokaryotic Cells

Simpler cells lacking membrane-bound organelles; Bacteria are prokaryotic.

Eukaryotic Cells

Complex cells with membrane-bound organelles; examples include animal, plant, fungal and protist cells

Cell Membrane

Selectively permeable, made of a bilayer of phospholipids, proteins, and steroids

Ribosomes

Help in Protein synthesis; made of protein and rRNA; subunits vary slightly in size between prokaryotes and eukaryotes

Endoplasmic Reticulum

Network of membrane channels in eukaryotes; Rough ER synthesizes proteins; Smooth ER synthesizes lipids and detoxifies.

Golgi Complex

Modifies and packages proteins for transport.

Lysosomes

Membrane-bound sacs containing hydrolytic enzymes for intracellular digestion.

Vacuoles

Membrane-bound sacs for storage and water regulation.

Mitochondria

Organelles that produce energy for the cell through cellular respiration.

Chloroplasts

Organelles in plants and algae that carry out photosynthesis.

Water Potential

The potential energy of water in a solution or the ability of water to do work; water flows from greater to lesser water potential.

Hypertonic

A solution with a high solute concentration.

Hypotonic

A solution with a lower solute concentration.

Endosymbiosis hypothesis

States that membrane-bound organelles were once free-living prokaryotes absorbed by a larger prokaryote.

Na+/K+ pump

Membrane protein which requires ATP to move molecules from areas of low concentration to high concentration; assists with active transport

diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration.

osmosis

Diffusion of water down its concentration gradient across a membrane.

Enzymes

Biological catalysts that speed up chemical reactions by lowering the activation energy.

Active Site

The region where the substrate binds on the enzyme.

Competitive Inhibitor

Molecule similar in shape to the substrate that competes for the active site.

Noncompetitive (Allosteric) Inhibitor

Molecule that binds to a different site on the enzyme, altering its shape and function.

Cofactor/Coenzyme

Inorganic/organic molecules that increase efficiency of enzyme-catalyzed reactions.

Activation Energy (EA)

The energy required to reach a transition state and start a chemical reaction.

Endergonic Reactions

Reactions that require an energy input.

Exergonic Reactions

Reactions that release energy.

Coupled Reactions

Pairing of an exergonic reaction with an endergonic reaction to allow the controlled transfer of energy.

Adenosine Triphosphate (ATP)

Main energy source for cells; the hydrolysis of ATP releases energy.

Photosynthesis

Process by which photoautotrophs convert light energy into chemical energy in the form of organic compounds.

Chlorophyll

Primary light absorbing pigment for Photosynthesis

Light-dependent reactions

First stage of photosynthesis in which light drives the production of ATP and NADPH. Occurs within the thylakoid membrane.

Light-independent reactions

Second stage of photosynthesis (also known as the Calvin cycle). ATP and NADPH are used to produce sugars. Occurs in the stroma of the Chloroplast.

Chemiosmosis

Use of a protein gradient and ATP synthase to produce ATP; required for both photosynthesis and cellular respiration.

Cellular Respiration

Process by which organisms release energy stored in the chemical bonds of organic molecules.

Glycolysis

Converts glucose into pyruvate, producing ATP and NADH.

Krebs Cycle (Citric Acid Cycle)

Completes the breakdown of glucose, releasing carbon dioxide, ATP, NADH, and FADH2.

Oxidative Phosphorylation

Uses the electron transport chain and chemiosmosis to generate most of the ATP in cellular respiration.

Fermentation

Regenerates electron carrier NAD+ from NADH in anaerobic conditions, allowing glycolysis to continue.

alcohol fermentation

Process by which pyruvate is reduced to ethanol (ethyl alcohol) and carbon dioxide; NAD+ is replenished.

lactic acid fermentation

Process by which pyruvate is reduced to lactate; NAD+ is replenished.

Cell Communication

The process through which cells can send, receive, and respond to chemical signals, or ligands

Autocrine signaling

Cell sends signal to itself.

Juxtacrine signaling

Signaling that depends on direct contact between sending cell and receiving cell.

Paracrine signaling

Cell secretes a ligand that travels a short distance, affecting local cells.

Endocrine signaling

Signaling that uses ligands that travel a long distance.

signal transduction

Series of processes and molecular changes that convey a signal from a receptor to a cell's DNA or machinery

ligand

A small signal molecule that binds to a larger receptor molecule.

Homeostasis

Maintenance of a stable internal environment through chemical processes within an organism (usually regulated by negative feedback).

apoptosis

Programmed cell death.

chromatid

Each half of the chromosome (which are connected) after DNA replication.

centromere

The region of a chromosome to which spindle fibers attach during cell division.

Meiosis

A process that creates four genetically different haploid gametes from a diploid somatic cell.

Mitosis

A process that creates two genetically identical diploid somatic cells from one diploid somatic cell.

diploid

The complete set of organisms chromosomes for growth; twice the number in gametes. Number represented as 2n.

haploid

Having one set of chromosomes, as seen in games produced in meiosis, 1n.

gene

Segment of DNA that codes for a protein.

allele

Version of a gene.

genetic recombination (crossing-over)

Process during Prophase 1 in which genetic material on homologous chromosomes is exchanged to produce unique combination of alleles.

law of segregation

States that the two alleles for a character separate during gamete formation.

law of independent assortment

States that each pair of alleles segregates independently of other pairs of alleles during gamete formation.

Linked Genes

Genes nearby each other on the chromosomes and tend to be inherited together into the next generation.

Non-nuclear inheritance

Traits inherited by genes from the mitochondria or chloroplast.

Pyrimidines

Thymine, uracil, and cytosine are all in this class of macromolecules.

Purines

Adenine and guanine are in this class of macromolecules.

Evolution

A change in the genetic makeup of a population over time, with increased or decreased allele frequencies.

Ecology

Scientific study of interactions between organisms and their environment.

karyotype

A display of the chromosome pairs of a cell arranged by size and shape.

Antiparallel structure

The strands of DNA that run in opposite directions, with the 5’ phosphate group of one of the strands opposite to the other strand.

Fluid mosaic model

The arrangement of cell membranes where their components have the property to move (fluidity) and in a diverse composition (mosaic).

Genetic Drift

A change in the allele frequency of a population as a result of chance events rather than natural selection.

Transcription factors

Proteins in eukaryotes that help RNA polymerase bind to the promoter and start transcription

Heterotrophs

An organism that cannot produce its own food, instead taking nutrition from other sources of organic carbon, mainly plant or animal matter.

Autotrophs

An organism that can produce its own organic molecules from inorganic molecules.

Photolysis

The splitting of water molecules to strip electrons from the hydrogen atoms, producing H+ ions, electrons and Oxygen gas.

Transcription

Process to generate RNA from DNA using base pairing rules; occurs in the nucleus (eukaryotes) and cytoplasm (prokaryotes).

Translation

Process to generate proteins from mRNA with tRNA and ribosomes; occurs in the cytoplasm and rough ER.

Endocytosis

Process through which a cell absorbs solutes or macromolecules by engulfing them in vesicles at the cell surface.

Exocytosis

Process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane with the cell membrane.

Somatic cells

A cell of a living organism other than egg or sperm cells