Enzyme structure

Science

Definition

Enzymes are biological catalysts made of proteins that speed up chemical reactions by lowering activation energy. They have a specific 3D shape with an active site where substrates bind, following a lock-and-key or induced-fit model. Enzyme function depends on proper folding and can be affected by temperature, pH, and inhibitors.

Examples

  • Amylase in saliva breaking down starch into sugars
  • Lactase enzyme breaking down lactose in dairy products
  • DNA polymerase helping copy DNA during replication
Key Fact

Enzymes lower activation energy without being consumed in the reaction

Related Terms

Activation energy Catalysts Macromolecules Cell respiration

Study This Concept

Practice enzyme structure with free review games in these units:

AP Biology Unit 1: Chemistry of Life