Question

Write the role of HCL during digestion?

Answer 1

Consider the following explanation.

Explanation:

`"HCl"`, also known as hydrochloric acid, is responsible for activating the enzyme pepsinogen present in the stomach to pepsin. Pepsin works best in acidic conditions. Actually, the stomach contains pepsinogen, `"HCl"`, and mucus and collectively, these substances constitute the stomach juice called gastric juice.

Now, this gastric juice is responsible for the digestion of protein contents in the food. If food containing more protein enters in the oral cavity, a signal is sent to stomach to secrete more of the gastric juice.

(What actually happens is that the mucus present in this juice prevents the pepsin from being activated when there is no food to be digested and also forms a lining on the stomach walls so that the acid may not digest them.)

When however, more proteinaceous food enters for digestion, `"HCl"` readily activates pepsinogen to its active form, pepsin, which readily breaks the peptide bonds in the food, hence digesting the substance.