AP Biology Lecture Notes

These flashcards cover key concepts from the AP Biology lecture, focusing on vocabulary and definitions critical for understanding biology.

Element

A substance that cannot be broken down into simpler substances by chemical means.

Trace Elements

Elements required by an organism only in small amounts, e.g., iron (Fe), iodine (I), copper (Cu).

Atom

The smallest unit of an element that retains the properties of that element.

Nucleus

The core of an atom containing protons and neutrons.

Isotope

Atoms with the same number of protons but different numbers of neutrons.

Ionic Bond

A bond formed between metal and non-metal atoms.

Covalent Bond

A bond formed between non-metal atoms by sharing electrons.

Hydrogen Bond

A weak attraction between a hydrogen atom and another electronegative atom.

Polarity

The distribution of electrical charge over the atoms joined by the bond.

Cohesion

The tendency of water molecules to stick to each other.

Adhesion

The tendency of water molecules to stick to other substances.

Capillary Action

The ability of water to rise in narrow spaces against gravity.

Surface Tension

The cohesive force at the surface of water that prevents it from breaking easily.

pH

A measure of the acidity or basicity of a solution.

Organic Compounds

Compounds that contain carbon and are typically associated with living organisms.

Monosaccharides

The simplest form of carbohydrates, e.g., glucose.

Disaccharides

Sugars formed from two monosaccharides, e.g., sucrose.

Polysaccharides

Large carbohydrate molecules composed of many monosaccharides, e.g., starch.

Amino Acids

Building blocks of proteins containing C, H, O, N, and sometimes S.

Peptide Bond

The bond formed between two amino acids when they are linked together.

Macromolecules

Large molecules formed by the joining of smaller subunits called monomers.

DNA

Deoxyribonucleic acid, the molecule that carries genetic information.

RNA

Ribonucleic acid, a molecule that helps in protein synthesis.

Mutation

A change in a DNA sequence that can lead to changes in phenotype.

Natural Selection

The process whereby organisms better adapted to their environment tend to survive and produce more offspring.

Ecosystem

A biological community interacting with its physical environment.

Biochemical Evidence

Molecular data that support evolutionary theory, showing genetic similarities among species.

Speciation

The process by which new species arise.

Endemic Species

Species that are native to and found only within a specific geographic area.