Enzymes, Metabolism, & ATP Test

Primary Structure

The sequence of amino acids in a polypeptide chain.

Secondary Structure

The local folding of the polypeptide chain into structures like alpha-helices and beta-sheets, stabilized by hydrogen bonds.

Tertiary Structure

The overall three-dimensional shape of a polypeptide chain, determined by interactions between side chains (R groups).

Quaternary Structure

The arrangement of multiple polypeptide chains to form a functional protein.

Peptide Bond

The bond formed between the carboxyl group of one amino acid and the amino group of the next amino acid.

Hydrogen Bond

An attraction between an H atom of one amino acid and an O atom from another amino acid in the chain.

Ionic Bond

An attraction between oppositely charged atoms.

Hydrophobic Interactions

Dispersion forces attractions between nonpolar groups.

Disulfide Bond

A covalent bond between two sulfur atoms.

Denaturation

The process of altering the structure of a protein, leading to loss of function.

Buffer

A solution that resists changes in pH.

Activation Energy

The minimum amount of energy needed for reactions to form products in a chemical reaction.

Exergonic Reaction

A reaction that releases energy.

Endergonic Reaction

A reaction that absorbs energy.

Competitive Inhibition

A type of inhibition where a molecule competes with the substrate for the active site.

Non-competitive Inhibition

A type of inhibition where a molecule binds to a site other than the active site, reducing the enzyme's activity.

Optimal Temperature

The temperature at which an enzyme functions best.

Optimal pH

The pH at which an enzyme functions best.

Chemical Potential Energy

The energy stored in the chemical bonds of molecules.

Reactant

A substance that undergoes a chemical change.

Product

A substance formed as a result of a chemical reaction.