Why does the action of salivary amylase stop in stomach?
Open in App
Solution
Salivary amylase, like most other enzymes, is a protein. Its action is most effective at a pH of 6.5 - 7.0. Under conditions more acidic or basic than that, the protein folding changes, which causes the molecule to become less effective as an enzyme.
Typically the pH in the stomach is around 1.0 to 2.0, which is extremely acidic. This level of acidity causes salivary amylase's protein structure to denature and change shape. Consequently, salivary amylase does not function once it enters the stomach.