Question

Where are proteins first digested in the alimentary canal?

Options

• small intestine

• oesophagus

• mouth

• stomach

Answer 1

stomach

Explanation:

The chemical digestion of proteins initiates exclusively in the stomach. The inner lining of the stomach contains gastric glands that secrete hydrochloric acid (HCl) and an inactive enzyme called pepsinogen. The strongly acidic environment created by HCl activates pepsinogen to its active form, pepsin, which begins breaking down large protein chains into smaller fragments called peptones and peptides.