AP Biology Ultimate Guide

Elements

Substances that cannot be broken down into simpler substances by chemical means, such as oxygen (O), carbon (C), hydrogen (H), and nitrogen (N).

Trace Elements

Elements required by an organism in very small quantities, like iron (Fe), iodine (I), and copper (Cu).

Atoms

The unit of life and building blocks of the physical world, consisting of protons, neutrons, and electrons.

Compounds

Consist of two or more elements held together by chemical bonds like ionic, covalent, or hydrogen bonds.

Hydrogen Bonds

Weak chemical bonds between a hydrogen atom and another electronegative atom.

Acids and Bases

Solutions characterized by their hydrogen ion (H+) or hydroxide ion (OH-) concentrations, measured on the pH scale.

Organic Molecules

Molecules containing carbon, essential for life, including carbohydrates, proteins, lipids, and nucleic acids.

Carbohydrates

Organic compounds with a ratio of approximately 1:2:1 of carbon, hydrogen, and oxygen, categorized as monosaccharides, disaccharides, or polysaccharides.

Proteins

Important for structure and function, composed of amino acids with different R-groups, categorized based on polarity.

Polypeptides

Chains of amino acids forming proteins, with primary, secondary, tertiary, and quaternary structures.

Lipids

Consist of carbon, hydrogen, and oxygen, including triglycerides, phospholipids, and steroids, crucial for cell membranes and energy storage.

Nucleic Acids

Molecules made up of nucleotides, like DNA and RNA, containing genetic information and essential for protein synthesis.

Cell Surface Markers

Glycoproteins and glycolipids exposed on the extracellular surface of cells, involved in cell recognition and adhesion.

Nucleus

Largest organelle directing cell activities, housing DNA organized into chromosomes, containing the nucleolus for rRNA synthesis and ribosome assembly.

Ribosomes

Sites of protein synthesis, composed of large and small subunits, can be free-floating or attached to the endoplasmic reticulum.

Endoplasmic Reticulum (ER)

Continuous channel providing support and transportation, rough ER with ribosomes and smooth ER synthesizing lipids and detoxifying chemicals.

Golgi Complex

Modifies, processes, and sorts proteins synthesized by ribosomes, packages products into vesicles for distribution out of the cell.

Mitochondria

Power stations converting organic molecules into ATP, with inner and outer membranes, cristae, and matrix.

Lysosomes

Contain digestive enzymes to break down organelles, debris, or particles, formed from vesicles and essential in apoptosis.

Cytoskeleton

Network of protein fibers determining cell shape, including microtubules and microfilaments for cellular division and movement.

Plant Cells

Differ from animal cells with a cell wall, chloroplasts, central vacuole, and absence of centrioles.

Passive Transport

Movement of molecules across the membrane without energy input, including simple diffusion and facilitated diffusion.

Osmosis

Movement of water across a selectively permeable membrane, influenced by tonicity and water potential.

Active Transport

Movement of molecules against the concentration gradient, requiring energy input, such as the sodium-potassium pump.

Enzymes

Biological catalysts speeding up reactions by lowering activation energy, specific to substrates, forming enzyme-substrate complexes.

Factors Affecting Enzyme Activity

Temperature, pH, and substrate concentration influencing enzyme function and reaction rates.

Enzyme Regulation

Control of enzymatic activity through factors like competitive inhibition and allosteric regulation.

Allosteric Inhibitor

An inhibitor that binds to an allosteric site on an enzyme, causing a change in the enzyme's shape and preventing it from functioning at its active site.

Noncompetitive Inhibition

A type of inhibition where the inhibitor binds to a site other than the active site of the enzyme, leading to enzyme distortion and the inability to catalyze the reaction.

Adenosine Triphosphate (ATP)

A molecule consisting of adenosine bonded to three phosphates, serving as the primary energy carrier in cells.

Cellular Respiration

The process of breaking down sugar to produce ATP, occurring in the presence of oxygen (aerobic respiration) or in the absence of oxygen (anaerobic respiration).

Photosynthesis

The process by which light energy is converted into chemical energy, involving the conversion of carbon dioxide and water into glucose and oxygen.

Chloroplast

Organelles found in plant cells where photosynthesis takes place, containing structures like the stroma, grana, and thylakoids.

Glycolysis

The initial stage of aerobic respiration where glucose is broken down into pyruvic acid, producing ATP and NADH.

Acetyl-CoA

A molecule formed from pyruvic acid during aerobic respiration, entering the Krebs cycle to generate more ATP.

Krebs Cycle

Also known as the citric acid cycle, a series of reactions in aerobic respiration that produce ATP, NADH, and FADH2.

Oxidative Phosphorylation

The final stage of aerobic respiration involving the electron transport chain and chemiosmosis to produce ATP from NADH and FADH2.

Glycolysis

The process of breaking down glucose to produce energy in the form of ATP, pyruvates, and NADH.

Fermentation

A metabolic process that occurs in the absence of oxygen, producing either lactic acid or ethanol as byproducts.

Cell Communication

The process by which cells detect and respond to environmental signals.

Signal Transduction

The transmission of external signals into the cell to elicit a cellular response.

Homeostasis

The maintenance of stable internal conditions within an organism.

Cell Cycle

The series of events that take place in a cell leading to its division and duplication.

Mitosis

The process of cell division that results in two identical daughter cells.

Haploid

A cell containing only one set of chromosomes.

Diploid

A cell containing two sets of chromosomes.

Gregor Mendel

The father of genetics who discovered the basic principles of heredity through pea plant experiments.

Recombination Frequency

The percentage of recombination determined by adding up recombinants and dividing by the total number of offspring.

Linkage Mapping

Mapping of linkage groups where each map unit equals 1 percent recombination, based on the frequency of crossing-over between linked alleles.

Sex-Linked Traits

Traits carried on sex chromosomes, such as color blindness and hemophilia, with most found on the X chromosome.

Barr Bodies

Inactivated X chromosomes in female cells, visible as dark-staining bodies in the nucleus.

Inheritance Patterns

Include incomplete dominance, codominance, polygenic inheritance, and non-nuclear inheritance through mitochondria.

Pedigrees

Special family trees showing genetic traits, helping determine if traits are recessive, dominant, or sex-linked.

Meiosis

The process of producing gametes involving two rounds of cell division - meiosis I and meiosis II.

DNA Structure

DNA consists of nucleotides with a deoxyribose sugar, phosphate, and nitrogenous base, forming a double helix with complementary base pairing.

Genome Structure

All DNA for a species is its genome, organized into chromosomes wrapped around histones and grouped into nucleosomes.

DNA Replication

The process of copying DNA involving unwinding, replication fork formation, leading and lagging strand synthesis, and conservation of half the original molecule in each new one.

DNA Helicase

Enzyme that unwinds the double helix into two strands.

DNA Polymerase

Enzyme that adds nucleotides to an existing DNA strand.

DNA Ligase

Enzyme that brings together Okazaki fragments during DNA replication.

Topoisomerase

Enzyme that cuts and rejoins the DNA helix to relieve tension.

RNA Primase

Enzyme that catalyzes the synthesis of RNA primers during DNA replication.

Transcription

Process of making an RNA copy of a DNA code.

Translation

Process of making a protein from an RNA template.

RNA

Single-stranded nucleic acid with ribose sugar and uracil base.

Exons

Regions in RNA that express the genetic code.

Introns

Noncoding regions in RNA that are removed during splicing.

Operon

Functional unit of DNA in bacteria consisting of structural genes, promoter, operator, and regulatory gene.

Mutation

Error in the genetic code that can result from various factors.

Recombinant DNA

DNA created by combining DNA from different sources.

Polymerase Chain Reaction (PCR)

Laboratory technique to amplify DNA segments.

Natural Selection

Mechanism of evolution based on genetic variation and environmental pressure.

Mutation and Reproduction

Mutations that do not kill an organism before reproduction can be passed on to the next generation.

Survival of the Fittest

Traits that enhance an individual's reproductive success contribute to evolutionary fitness.

Sexual Selection

Females choosing mates based on specific traits, like a large and beautiful tail, is an example of sexual selection.

Genetic Drift

A process causing genetic changes in a population, distinct from natural selection, often due to bottleneck or founder effects.

Gene Flow

Movement of genes between populations through migration of individuals.

Directional Selection

A type of natural selection where one extreme phenotype is favored.

Stabilizing and Disruptive Selection

Stabilizing selection eliminates extreme traits, while disruptive selection favors multiple extremes.

Artificial Selection

Humans directly influencing the variation in other species through selective breeding.

Reproductive Isolation

Necessary for species to diverge, preventing interbreeding between populations.

Divergent Evolution

Occurs when populations with different variations and environmental pressures evolve into distinct species.

Punctuated Equilibrium

Rapid divergent evolution following a period of stasis.

Pre-zygotic and Post-zygotic Barriers

Prevent fertilization and hinder hybrid offspring's ability to reproduce, respectively.

Convergent Evolution

Unrelated species develop similar traits due to comparable selective pressures.

Allopatric and Sympatric Speciation

Allopatric speciation involves geographic isolation, while sympatric speciation occurs without physical separation.

Hardy-Weinberg Law

States that genotype frequencies in a population remain constant if certain conditions are met.

Endotherms and Ectotherms

Endotherms produce internal heat, while ectotherms rely on external sources for temperature regulation.

Instinct and Learning

Instinct is innate behavior, while learning involves behavioral changes due to experiences.

Imprinting

Offspring forming attachments to the first moving object they see in the absence of their mother.

Circadian Rhythms

Internal clocks regulating behaviors in animals and plants.

Symbiotic Relationships

Mutualism benefits both, commensalism benefits one without harm, and parasitism harms the host.

Tropisms

Plant responses to stimuli like light (phototropism), gravity (gravitropism), and touch (thigmotropism).

Ecology Levels

Biosphere, ecosystem, community, and population represent different ecological scales.

Primary Productivity

Gross productivity from photosynthesis and net productivity after cellular energy needs are met.

Keystone Species

Organisms crucial for ecosystem stability.

Simpson’s Diversity Index

Formula to calculate diversity based on species abundance in a population.

Population Growth

Represented by birth rate minus death rate divided by population size.

Carrying Capacity

Maximum population size a habitat can sustain.

Exponential Growth

Rapid population increase in ideal conditions, depicted by a J-shaped curve.