Which statement correctly describes enzymes?

Which statement correctly describes enzymes?

• A. Nucleic acids that store energy
• B. Lipids that insulate cells
• C. Inorganic minerals
• D. Proteins that speed up chemical reactions

Answer: (D)

Enzymes are biological catalysts that accelerate chemical reactions by lowering the activation energy needed to reach the transition state. Most enzymes are proteins with a specific 3D shape that creates an active site where a substrate binds. This binding helps orient the molecules and stabilizes the transition state, allowing the reaction to proceed faster without the enzyme being consumed. Enzymes are highly substrate-specific and can be affected by factors like temperature and pH, which can alter their shape and function; some also require cofactors or coenzymes to work. By contrast, nucleic acids store genetic information, lipids mainly store energy and insulate, and inorganic minerals are non-living nutrients. Describing enzymes as proteins that speed up chemical reactions captures the essential idea.

Enzymes are biological catalysts that accelerate chemical reactions by lowering the activation energy needed to reach the transition state. Most enzymes are proteins with a specific 3D shape that creates an active site where a substrate binds. This binding helps orient the molecules and stabilizes the transition state, allowing the reaction to proceed faster without the enzyme being consumed. Enzymes are highly substrate-specific and can be affected by factors like temperature and pH, which can alter their shape and function; some also require cofactors or coenzymes to work. By contrast, nucleic acids store genetic information, lipids mainly store energy and insulate, and inorganic minerals are non-living nutrients. Describing enzymes as proteins that speed up chemical reactions captures the essential idea.