Process of Digestion: In Stomach -
- The stomach stores food for 4-5 hours.
- The food mixes thoroughly with the acidic gastric juice in the stomach by the churning movements of its muscular wall and is called the chyme.
- The proenzyme pepsinogen, on exposure to hydrochloric acid, gets converted into the active enzyme pepsin, the proteolytic enzymes of the stomach.
- Pepsin converts proteins into proteases and peptones (peptides).
- The mucus and bicarbonates present in the gastric juice play an important role in lubrication and protection of the mucosal epithelium from excoriation by the highly concentrated hydrochloric acid.
- HCl provides the acidic pH (pH 1.8) optimal for pepsin.
- Rennin is a proteolytic enzyme found in gastric juice of infants which helps in the digestion of milk proteins.
- Small amounts of lipases are also secreted by gastric glands.
HCl provides the acidic pH (pH 1.8) optimal for pepsin. Hence, the correct answer is option c.
View full answer