AP Biology: Energy and Metabolism Vocabulary

Chemical energy

Energy stored in the bonds of molecules that can be released during chemical reactions.

Metabolic pathway

A series of enzyme controlled reactions that convert a starting molecule into a final product.

Exergonic

A reaction that releases energy because products have less free energy than reactants.

Endergonic

A reaction that requires energy input because products have more free energy than reactants.

Catabolism

Metabolic processes that break down complex molecules and release energy.

Anabolism

Metabolic processes that build complex molecules and require energy.

Energetic coupling

The use of energy from exergonic reactions to drive endergonic reactions.

Enzyme

A biological catalyst that speeds up chemical reactions.

Catalyst

A substance that increases reaction rate without being consumed.

Activation energy

The minimum energy needed to initiate a chemical reaction.

Substrate

The reactant molecule that an enzyme acts on.

Active site

The specific region of an enzyme where the substrate binds.

Denature

To alter a protein’s shape so it no longer functions properly.

Inhibitor

A molecule that reduces enzyme activity.

Allosteric site

A regulatory site on an enzyme separate from the active site.

Activator

A molecule that increases enzyme activity.

Photosystem

A group of pigments and proteins that capture light energy during photosynthesis.

ATP synthase

An enzyme that produces ATP using energy from a proton gradient.

Photophosphorylation

The production of ATP using light energy during photosynthesis.

Cellular respiration

A metabolic process that breaks down glucose to generate ATP.

Substrate level phosphorylation

ATP formation by direct transfer of a phosphate group to ADP.

Oxidative phosphorylation

ATP production driven by the electron transport chain and chemiosmosis.

Chemiosmosis

The movement of protons across a membrane that drives ATP synthesis.

Fermentation

An anaerobic process that regenerates NAD to allow glycolysis to continue.