What effect does an enzyme have on the rate of a chemical reaction?

Enzymes are biological catalysts that significantly enhance the rate of chemical reactions in biological systems. They achieve this by lowering the activation energy required for the reaction to proceed. When an enzyme binds to its substrate, it forms an enzyme-substrate complex that stabilizes the transition state, making it easier for the reaction to occur. This results in a faster conversion of substrates to products compared to reactions that occur without the presence of the enzyme.

Additionally, enzymes often function under optimal conditions specific to their environment, such as temperature and pH, allowing for efficient catalytic activity. Therefore, because enzymes accelerate the reactions they catalyze, the correct answer indicates that they increase the rate of the reaction.