Which enzyme breaks down starch in the human digestive system?

• A. Protease
• B. Lipase
• C. Nuclease
• D. Amylase

Answer: (D)

Starch digestion relies on amylase, an enzyme that hydrolyzes the alpha-1,4 glycosidic bonds in starch to produce smaller sugars like maltose and dextrins, paving the way for absorption as glucose. In humans, this process starts in the mouth with salivary amylase and continues in the small intestine with pancreatic amylase. The other enzymes listed have different roles: proteases digest proteins, lipases digest fats, and nucleases digest nucleic acids. So amylase is the enzyme responsible for breaking down starch in the digestive system.