Enzymes are globular proteins that act as biological catalysts, speeding up reaction rates. They have an active site that substrates bind to, lowering the activation energy of reactions. Each enzyme's active site has a unique three-dimensional shape and charge distribution complementary to its substrate. This precise fit between the active site and substrate allows chemical reactions to occur. Environmental factors like temperature, pH, and substrate concentration can alter an enzyme's structure and activity by changing bonds within its active site. Denaturation is when an enzyme loses its biological function due to a change in its tertiary structure. Lactase is used to produce lactose-free milk by breaking down the milk sugar lactose into simpler sugars, allowing those with