Which of the following is NOT an example of mechanical digestion? MULTIPLE CHOICE.

A. Amylase breaking down starch in the mouth

B. Churning of food in the stomach

C. Segmentation of food in the small intestine

D. Chewing of food in the mouth

C segmentation of food in the small intestine

Explanation:

mechanical digestion occurs only in the mouth and that is the only one that does not occur in the mouth.Even though Both mechanical and chemical digestion occur in the mouth. ... The muscles in the stomach walls churn the bolus (mechanical), allowing it to mix with digestive enzymes and gastric acids (chemical). This process converts the bolus into a liquid called chyme. Digestion continues in the stomach for several hours. so c is the answer

a neutral ph of 7 and normal organism temperature is needed for a certain enzyme to be effective.  

what would happen to the enzyme if the ph and/or temperature fluctuate greatly from the norm?  

a.the enzyme’s hydrogen bonds will break.  

b.the activation energy will increase.  

c.more product will be formed.

d.the ideal temperature and ph for the enzyme function will decrease.