The gastric juice contains three substances; hydrochloric acid, the enzyme pepsin and mucus. Functions:
(a) Hydrochloric acid: It makes the medium of gastric juice acidic so that the enzyme pepsin can digest the proteins properly and also kills any bacteria that might have entered the stomach with food.
(b) Pepsin: The enzyme pepsin digests the proteins present in the food and converts them into smaller molecules.
(c) Mucus: The mucus helps to protect the stomach wall from its own secretions of hydrochloric acid
