Where are proteins first digested in the alimentary canal ? (a) small intestine (b) oesophagus (c) mouth (d) stomach
Option d, stomach
Protein digestion begins in the stomach with the action of an enzyme called pepsin. Pepsin is the active protein-digesting enzyme of the stomach. When pepsin acts on the protein molecule, it breaks the bonds that hold the protein molecule together, called peptide bonds. When these bonds are broken, you get chains of amino acids linked together called polypeptides. These polypeptides then move into your small intestine, where digestion will be completed by additional enzymes.