| Term | Definition |
| Enzymes | proteins that act as biological catalysts |
| Catalyst | A substance that speeds the rate of a chemical reaction by lowering the amount of activation energy required |
| Activation Energy | the minimum amount of energy required to start a chemical reaction |
| Substrate | the reactant that the enzyme binds |
| Enzyme-Substrate Complex | when the enzyme is bound to the substrate |
| Product | What is created while the enzyme is bound to the substrate |
| Competitive Inhibitor | An enzyme inhibitor that competes with substrate for binding at the active site of the enzyme. When the inhibitor is bound, no product can be made, overcome by increase substrate concentration |
| Non-Competitive Inhibitor | An enzyme inhibitor that binds at a site other than the active sit of an enzyme (binds at an allosteric site) making it unusable. Reversible, do not mimic substrate, not overcome by increase substrate concentration |
| Active Site | The region of the enzyme that binds the substrate |
| Allosteric Site | A site on an enzyme other than the active site, to which a specific substance binds |
| Allosteric Inhibitor | binds to enzyme at an allosteric site and makes the enzyme inactive (enzyme can't bind to substrate with an allosteric inhibitor in it) |
| Reversible Inhibition | Inhibition that can be reversed, enzyme inhibitor attaches by weak bonds |
| Irreversible Inhibition | an inhibitor that binds covalently and cannot be removed |
| Feedback Inhibition | A method of metabolic control in which the end product of a metabolic pathway acts as an inhibitor of an enzyme within that pathway. End product acts as an inhibitor |