which of the following is corrext pairing of site of action and substrate of rennin

1. mouth-starch
2. stomach-fat
3. stomach-caseinogen
4. small intestine -fat

Hello Student
Correct answer is 3. stomach – Caseinogen
Renin occurs in gastric juice and is a constituent of rennet. It coagulates milk by converting caseinogen to casein.

The correct answer is (3) Stomach-Caseinogen

For example, curd formation (rennet coagulation) is a reaction that occurs upon adding the enzyme rennin to milk. In this reaction, the substrate is a milk protein (e.g., casein) and the enzyme is rennin.