Which enzyme digests proteins in the stomach?

Which enzyme digests proteins in the stomach?

• A. Amylase
• B. Pepsin
• C. Lipase
• D. Maltase

Answer: (B)

Proteins are digested in the stomach by a protease that is activated by the acidic gastric environment. This enzyme is pepsin. It is secreted as pepsinogen by chief cells and converted to active pepsin by hydrochloric acid from parietal cells. Once active, pepsin cleaves peptide bonds in proteins, producing smaller polypeptides and peptides. It works best at the stomach’s very low pH, making it the primary enzyme for initiating protein digestion there. The other enzymes shown target other foods: amylase digests carbohydrates like starch, maltase digests maltose in the small intestine, and lipase digests fats. They don’t digest proteins in the stomach.

Proteins are digested in the stomach by a protease that is activated by the acidic gastric environment. This enzyme is pepsin. It is secreted as pepsinogen by chief cells and converted to active pepsin by hydrochloric acid from parietal cells. Once active, pepsin cleaves peptide bonds in proteins, producing smaller polypeptides and peptides. It works best at the stomach’s very low pH, making it the primary enzyme for initiating protein digestion there.

The other enzymes shown target other foods: amylase digests carbohydrates like starch, maltase digests maltose in the small intestine, and lipase digests fats. They don’t digest proteins in the stomach.