Which of the following is not true of saliva?
a. cleanses the mouth
b. contains enzymes that begin the breakdown of proteins
c. moistens food and aids in compacting of the bolus
d. dissolves food chemicals so they can be tasted

The answer is B. contains enzymes that begin the breakdown of proteins.

Saliva is watery substance secreted by salivatory glands. It cleanses the mouth and maintenance oral hygiene. It moistens the food, so the created food bolus could easier pass into the esophagus. It also carries food chemicals to taste receptors so they can be tested. It contains enzymes involved in the food digestions. Some of them are amylase, which begins the breakdown of the starch, and lipase, which begins the breakdown of triglycerides. There are no enzymes in the saliva that break down proteins.