In the buccal cavity of human being digestion of which one of the following get started?

Question

UnlockIAS · Accepted Answer

Correct — C, Carbohydrate. In the buccal cavity (mouth), saliva contains the enzyme salivary amylase (ptyalin), which begins breaking down cooked starch (a carbohydrate) into maltose. So carbohydrate is the macronutrient whose digestion starts in the mouth.

Why the other options are wrong — (a) Protein digestion begins in the STOMACH, where the enzyme pepsin (activated by hydrochloric acid) acts — not in the mouth.  (b) Fat digestion mainly begins in the SMALL INTESTINE, where bile emulsifies fat and pancreatic lipase acts; the mouth has no significant role in fat digestion.  (d) Wrong — carbohydrate digestion clearly starts in the mouth through salivary amylase, so a definite option is correct.

Concept: Digestion of the three macronutrients begins at different points along the alimentary canal. Carbohydrate (starch) digestion starts in the mouth with salivary amylase (ptyalin); protein digestion starts in the stomach with pepsin; and fat digestion mainly starts in the small intestine with bile and pancreatic lipase. The mouth handles only carbohydrate chemically (besides mechanical chewing).

State PCS 2019 Q35 — Science & Technology PYQ with Answer

State PCS 2019 Q35 — Science & Technology PYQ with Answer