3.1.A—Explain how enzymes affect the rate of biological reactions

Explain how enzymes affect the rate of biological reactions.

• The structure and function of enzymes contribute to the regulation of biological processes. Enzymes are proteins that are biological catalysts that facilitate chemical reactions in cells by lowering the activation energy.
• For an enzyme-mediated chemical reaction to occur, the shape and charge of the substrate must be compatible with the active site of the enzyme. This is illustrated by the enzymesubstrate complex model.