Breakdown of substances is called what?

• A. Cardiomyopathy
• B. Catabolism
• C. Cardiodynia
• D. Cardiomegaly

Answer: (B)

Catabolism is the breakdown of substances within metabolism. It refers to breaking larger molecules into smaller ones, releasing energy that cells can use. Think of digestion turning proteins into amino acids or cellular respiration converting glucose into carbon dioxide and water—the energy released powers other cellular activities. The other terms are about the heart: cardiomyopathy is disease of the heart muscle, cardiodynia means heart-related chest pain, and cardiomegaly is an enlarged heart. Since the question asks for the term for breaking down substances, catabolism is the precise fit.