AP Bio Notes

Homeostasis

The process by which animals maintain stability in bodily systems while adapting to external changes.

Homozygous

Having two identical genes in a gene pair inherited from both parents.

Heterozygous

Having two different genes in a gene pair inherited from both parents.

Polygenic Inheritance

The inheritance pattern of a trait controlled by multiple genes, typically three or more.

Coupled Reactions

Reactions where the products of one reaction are used to drive another reaction.

Electronegativity

The measure of an atom's ability to attract shared electrons to itself.

Polarity

Property of molecules with distinct positive and negative poles that can attract or repel each other.

Monomer

A molecule capable of combining with others of the same kind to form a polymer.

Polymer

A large molecule composed of repeating units or monomers.

Isotope

Elements with the same atomic number but different atomic masses.

Isomer

Molecules with the same chemical formula but different structures.

Atomic Mass

The total number of protons and neutrons in an atom's nucleus.

Atomic Number

The number of protons in an atom's nucleus.

Cohesion

The tendency of water molecules to stick together.

Adhesion

The ability of water molecules to stick to other surfaces.

Capillary Action

The movement of a liquid in a narrow space against external forces like gravity.

Specific Heat

The amount of heat needed to raise the temperature of a substance by 1 degree.

Surface Tension

The tendency of liquid surfaces to minimize their surface area.

Universal Solvent

Water's ability to dissolve more substances than any other liquid.

Solute

The substance that is dissolved in a solution by a solvent.

Solvent

The substance that dissolves the solute in a solution.

Solution

A mixture of a solvent and solute.

Hydrogen Bond

The attraction between a partially negative oxygen atom and a partially positive hydrogen atom.

Hydrolysis

A chemical reaction where water breaks chemical bonds.

Dehydration Synthesis

The process of combining two molecules by removing a water molecule.

Meiosis

Process ensuring the formation of haploid gametes in sexually reproducing organisms, involving two rounds of cell division resulting in four genetically different daughter cells.

Mitosis

Process of cell division similar to meiosis 1, producing two genetically identical daughter cells through the stages of prophase, metaphase, anaphase, telophase, and cytokinesis.

Uracil

Nitrogenous base unique to RNA nucleotides, distinguishing RNA from DNA due to the presence of uracil in RNA.

Speciation

Formation of new species through isolation mechanisms preventing interbreeding, gene flow, and fertile reproduction, leading to the diversification of life forms.

Prezygotic Barriers

Mechanisms preventing the formation of fertilized eggs, such as habitat isolation, temporal isolation, behavioral isolation, mechanical isolation, and gamete isolation.

Postzygotic Barriers

Mechanisms hindering viable offspring production, including incompatibility of sperm and egg, hybrid sterility, and hybrid breakdown.

Allopatric Speciation

Speciation resulting from geographic isolation, leading to no gene flow between populations and exposure to different selection pressures.

Sympatric Speciation

Speciation due to reproductive isolation within a single population, caused by genetic mutations, habitat differentiation, and sexual selection.

Punctuated Equilibrium

Theory suggesting rapid evolution following long periods of stasis, triggered by changes in ecological conditions.

Adaptive Radiation

Evolutionary process filling empty ecological niches, allowing for the diversification of species.