Question

The environment of the small intestines is BASIC (pH is more than 7). When gastric protease enters the small intestine, the activity of the enzyme will most likely

A. Increase only
B. Increase then decrease
C. Decrease only
D. Remain the same

Answer 1

Gastric protease pepsinogen an inactive zymogen. It is activated by HCl (low pH) in the stomach into active pepsin. You have to be specific where in the small intestine, but generally since you indicate a basic environment, then it means that the enzyme will have a reduced activity due to an increased pH.

This is to say that pepsinogen needs a low pH of about 1,2 or 3 to be activated and if the pH is higher than 7, it will be most likely inactive once again.