Question

The stomach produces hydrochloric acid which increases the acidity of the stomach to the optimum pH for stomach enzymes to digest the food. However, digestive enzymes found in the small intestine are damaged by strongly acidic conditions. How does the body avoid damaging the digestive enzymes in the small intestine with this strongly acidic pH as the food passes out of the stomach?

a) The pancreas secretes alkaline substances to neutralize acidity.
b) The small intestine produces acidic conditions for enzyme activation.
c) The liver releases enzymes resistant to acidic environments.
d) The stomach lining protects the enzymes during the digestive process.

Answer 1

The pancreas secretes bicarbonate, an alkaline substance, into the small intestine to neutralize the acidity from the stomach, thereby protecting the digestive enzymes in the small intestine.

Step-by-step explanation:

The stomach produces hydrochloric acid, which creates a highly acidic environment essential for the digestive enzyme pepsin to break down proteins.

However, when the acidic stomach contents move into the small intestine, the acidity can harm the digestive enzymes present there, which function optimally in a basic environment.

To neutralize the strong acid and prevent damage, the pancreas secretes an alkaline substance, mainly bicarbonate, into the small intestine.

This alkaline secretion buffers the acidic gastric juice, neutralizing the acidity and creating a suitable pH for the enzymes in the small intestine, such as trypsin and chymotrypsin, to effectively digest proteins into amino acids.