Which statement about salivary amylase is true?

• A. It acts on starch to produce maltose
• B. It acts on protein to produce amino acids
• C. It acts on fat to produce fatty acids
• D. It acts on nucleic acids to produce nucleotides

Answer: (A)

Salivary amylase is a carbohydrate-digesting enzyme produced in the salivary glands. Its job is to start breaking down starch as soon as it enters the mouth. It cleaves the alpha-1,4 glycosidic bonds in starch, producing maltose (a disaccharide of glucose) and some smaller dextrins. That’s why the statement about acting on starch to produce maltose is true. It doesn’t act on proteins, fats, or nucleic acids—these are handled by proteases, lipases, and nucleases, respectively. In the stomach the enzyme is inactivated by acid, and carbohydrate digestion resumes later with pancreatic amylase in the small intestine, followed by final breakdown to glucose by brush-border enzymes.