What is the role of enzymes in chemical reactions?

Enzymes play a crucial role in biochemical reactions primarily by lowering the activation energy required to initiate those reactions. Activation energy is the minimum amount of energy needed for reactants to undergo a transformation into products. Enzymes act as biological catalysts, meaning they facilitate reactions without being consumed in the process. By lowering the activation energy, enzymes allow reactions to occur more quickly and efficiently at relatively lower temperatures and under milder conditions. This function is essential in biological systems, where quick and efficient metabolic processes are necessary for sustaining life.

In contrast, the other options do not accurately describe the role of enzymes: converting activation energy into kinetic energy or potential energy misrepresents how energy is utilized or transformed in a reaction. Furthermore, enzymes do not stop chemical reactions; rather, they accelerate reaction rates. This distinctive role of enzymes is fundamental to many biological processes, including digestion, metabolism, and DNA replication.