The process of mechanically and chemically breaking down food into smaller molecules is called __________.

• A. Metabolism
• B. Digestion
• C. Absorption
• D. Catabolism

Answer: (B)

Digestion is the process of mechanically and chemically breaking down food into smaller molecules. This includes physical actions like chewing and stomach churning, plus chemical actions from enzymes and acids that turn foods into absorbable units such as sugars, amino acids, and fatty acids. This step makes nutrients available for absorption and use in the body. Metabolism refers to all the body's chemical reactions, absorption is the movement of nutrients from the gut into the bloodstream, and catabolism is the breakdown of molecules within cells as part of metabolism—not the whole digestive process.