Which chemical in gastric juice digests proteins?

Which chemical in gastric juice digests proteins?

• A. Hydrochloric acid
• B. Pepsin
• C. Mucus
• D. Lipase

Answer: (B)

Proteins are digested in the stomach by a protease present in gastric juice. That enzyme is pepsin, which is released as an inactive form and activated by the acidic environment created by hydrochloric acid. Once active, pepsin cleaves peptide bonds within protein molecules, breaking them into smaller peptides. The acidity also helps unfold proteins, making their peptide bonds more accessible. Mucus protects the stomach lining rather than digesting proteins, and lipase targets fats rather than proteins. So pepsin is the correct enzyme for protein digestion in gastric juice.

Proteins are digested in the stomach by a protease present in gastric juice. That enzyme is pepsin, which is released as an inactive form and activated by the acidic environment created by hydrochloric acid. Once active, pepsin cleaves peptide bonds within protein molecules, breaking them into smaller peptides. The acidity also helps unfold proteins, making their peptide bonds more accessible. Mucus protects the stomach lining rather than digesting proteins, and lipase targets fats rather than proteins. So pepsin is the correct enzyme for protein digestion in gastric juice.