Enzymes: Biological Catalysts

A set of flashcards detailing key vocabulary and concepts related to enzymes, their functions, classifications, and regulation.

Enzyme

A biological catalyst made of proteins that speeds up reactions without being consumed.

Activation Energy

The energy barrier that must be overcome for a reaction to occur.

Active Site

The specific region of an enzyme where substrate binding and catalysis occur.

Substrate

A molecule that acts as a reactant in an enzymatic reaction.

Induced Fit Model

A model explaining how an enzyme changes its shape to accommodate a substrate upon binding.

Coenzyme

A non-protein organic molecule that assists enzymes in catalyzing reactions.

Zymogen

An inactive enzyme precursor that requires a biochemical change to become active.

Competitive Inhibitor

A substance that competes with the substrate for the active site of an enzyme.

Allosteric Regulation

Regulation of enzyme activity through binding of effectors at sites other than the active site.

Hydrolase

An enzyme that catalyzes the hydrolysis of substrates, breaking bonds with water.

Lyase

An enzyme that catalyzes bond-breaking reactions not involving water.

Isomerase

An enzyme that catalyzes the conversion of a molecule into its isomers.

Ligase

An enzyme that joins two molecules together by forming a bond.

Optimum Temperature

The temperature at which an enzyme shows maximum activity.

pH Optimum

The pH level at which an enzyme has the highest activity.

Feedback Regulation

A process where the end product of a metabolic pathway inhibits an earlier step.

Positive Allosteric Regulator

A molecule that enhances enzyme activity by binding to a site other than the active site.

Negative Allosteric Regulator

A molecule that reduces enzyme activity by altering the enzyme's conformation.

Cofactor

A non-protein substance that is required for an enzyme's biological activity.

Fat-Soluble Vitamins

Vitamins that can be stored in the body's membranes and are hydrophobic.

Water-Soluble Vitamins

Vitamins that cannot be stored in the body and are excreted if in excess.

Non-competitive Inhibitor

An inhibitor that binds to an enzyme at a site other than the active site and affects enzyme function.