What is the primary function of enzymes in biological systems?

• A. Catalyze chemical reactions by lowering activation energy
• B. Break down complex molecules into simpler ones
• C. Store genetic information
• D. Transport substances across cell membranes

Answer: (A)

The primary function of enzymes in biological systems is to catalyze chemical reactions by lowering the activation energy required for those reactions to occur. Enzymes are biological catalysts that speed up chemical reactions without being consumed in the process. By lowering the activation energy, enzymes enable reactions to proceed more quickly and efficiently, allowing metabolic processes to occur at rates compatible with life.

This catalytic action is fundamental for various biological functions, including digestion, metabolism, and DNA replication, among others. Enzymes achieve this by providing an active site where substrates can bind and be transformed into products, facilitating the conversion of reactants into products in a controlled manner that helps maintain homeostasis in cells.

Other options highlight different biological functions but do not accurately describe the primary role of enzymes. For instance, while some enzymes do play a role in breaking down complex molecules, not all enzymes are involved specifically in this process. Storing genetic information pertains more to nucleic acids than to enzymes, and the transportation of substances across cell membranes is primarily the function of proteins such as channels and transporters, rather than enzymes themselves.