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.

Water

A versatile molecule with unique properties due to hydrogen bonds, including cohesion, adhesion, and surface tension.

Acids and Bases

Solutions can be acidic (lots of H+ ions), basic (lots of OH- ions), or neutral (pH 7), measured on a pH scale.

Organic Molecules

Molecules containing carbon, essential for life, forming polymers like carbohydrates, proteins, lipids, and nucleic acids.

Carbohydrates

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

Proteins

Important for structure and function, made of amino acids, with different categories based on side chain polarity.

Lipids

Consist of carbon, hydrogen, and oxygen, including triglycerides, phospholipids, and steroids, serving various functions in the body.

Nucleic Acids

Molecules made 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, and containing the nucleolus for 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.

Golgi Complex

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

Mitochondria

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

Lysosomes

Organelles containing digestive enzymes to break down organelles, debris, or particles, essential in apoptosis.

Vacuoles

Fluid-filled sacs storing various substances in plant cells.

Peroxisomes

Organelles detoxifying substances, producing hydrogen peroxide, and breaking it down into oxygen and water.

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 substances across the membrane without energy input, including simple and facilitated diffusion.

Osmosis

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

Active Transport

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

Endocytosis

Process of engulfing substances by the cell membrane to form vesicles, including pinocytosis, phagocytosis, and receptor-mediated endocytosis.

Exocytosis

Process of expelling waste or secretion products from the cell by fusion of vesicles with the plasma membrane.

Bioenergetics

Study of how cells obtain and use energy.

Enzymes

Biological catalysts speeding up reactions by lowering activation energy, with specificity, active sites, and induced-fit.

Factors Affecting Enzyme Activity

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

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, distorting its shape and hindering its catalytic activity.

ATP (Adenosine Triphosphate)

A molecule consisting of adenosine bonded to three phosphates, storing a significant amount of energy in its phosphate bonds.

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 in the presence of sunlight.

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 in the cytoplasm.

Krebs Cycle

Also known as the citric acid cycle, a stage of aerobic respiration occurring in the mitochondria where acetyl-CoA is combined with oxaloacetate to produce ATP, NADH, and FADH2.

Oxidative Phosphorylation

The final stage of aerobic respiration involving the electron transport chain and chemiosmosis to produce ATP by utilizing the energy from high-energy electrons.

Chemiosmosis

The process where a proton gradient is used to generate ATP by allowing hydrogen ions to diffuse back into the matrix through ATP synthase, occurring in both photosynthesis and cellular respiration.

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 in living organisms.

Cell Cycle

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

Mitosis

The process of cell division resulting in two identical daughter cells.

Haploid

A cell containing one set of chromosomes.

Diploid

A cell containing two sets of chromosomes.

Gregor Mendel

The father of genetics known for his work on inheritance patterns in pea plants.

Recombination Frequency

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

Recombination 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, due to X-inactivation during embryonic development.

Inheritance Patterns

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

Pedigrees

Special family trees showing genetic inheritance patterns, 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, to create haploid cells.

DNA Structure

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

Genome Structure

All DNA in a species is its genome, organized into chromosomes wrapped around histones, forming euchromatin or heterochromatin.

DNA Replication

The process of copying DNA involving unwinding the double helix, forming a replication fork, and synthesizing new strands using DNA polymerase.

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 driven by genetic variation and environmental pressures.

Mutation

Genetic change that can be passed on to the next generation if it does not kill the organism before reproduction.

Survival of the fittest

Concept where traits leading to better reproductive success increase evolutionary fitness.

Sexual selection

Process where mate choice influences evolution, like females selecting males with specific traits.

Genetic drift

Random change in genetics of a population, not driven by natural selection, includes bottleneck and founder effects.

Gene flow

Transfer of genetic material between populations due to migration of individuals.

Directional selection

Type of natural selection favoring individuals at one extreme of a trait.

Divergent evolution

Process where populations become reproductively isolated and evolve into different species.

Punctuated equilibrium

Rapid divergent evolution following a period of stability.

Pre-zygotic barriers

Mechanisms preventing fertilization between different species.

Post-zygotic barriers

Factors hindering hybrid organisms from producing viable offspring.

Convergent evolution

Unrelated species develop similar traits due to shared selective pressures.

Allopatric speciation

Population isolation by a geographic barrier leading to the formation of new species.

Hardy-Weinberg law

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

Endotherms

Animals generating body heat internally through metabolism.

Imprinting

Behavior where offspring form strong attachments to the first moving object they see.

Circadian rhythms

Internal cycles like alarm clocks in animals and plants.

Pheromones

Chemical signals within a species affecting behavior.

Mutualism

Symbiotic relationship where both organisms benefit.

Photoperiodism

Plant response to changes in daylight and darkness.

Ecology

Study of interactions between living organisms and their environment.