How do enzymes affect the activation energy of a reaction?

Enzymes serve as biological catalysts that significantly lower the activation energy required for a chemical reaction to occur. Activation energy is the minimum energy required for reactants to transform into products, and without enzymes, many biochemical reactions would occur too slowly to sustain life. By providing an alternative reaction pathway, enzymes stabilize the transition state and facilitate the conversion of substrates to products more efficiently.

This reduction in activation energy allows reactions to proceed at a faster rate, enabling cells to carry out essential metabolic processes under mild conditions, such as normal temperature and pressure. Enzymes achieve this through various mechanisms, including forming temporary enzyme-substrate complexes and lowering the energy threshold for the reaction. Thus, the correct answer is that enzymes decrease the activation energy of a reaction, promoting quicker and more efficient biochemical transformations.