(i) Gastric juice contains HCl. It creates an acidic environment in the stomach, destroys bacteria and converts inactive enzymes into active enzymes.
(ii) Pepsin enzyme in gastric juice converts protein into peptone.
(iii) Renin enzyme in gastric juice converts milk casein to paracasein.
(iv) Gastric juice contains intrinsic factor. It absorbs vitamin B12.
(v) The gastric juice mucosa protects the stomach wall. So the stomach does not digest itself.
(vi) Toxic substances, heavy metals, alkaloids etc. are excreted from the body with gastric juice.