Question

How do carbohydrates, proteins and fats get digested in human beings?

• A. They all are digested only in the stomach.
• B. They all are digested only in small intestine.
• C. Carbohydrate digestion starts at mouth. Protein and fat digestion start at stomach and digestion of all three biomolecules completes at small intestine.
• D. None of the above.

Answer 1

Answer: (C)

Carbohydrate digestion starts at mouth. Protein and fat digestion start at stomach and digestion of all three biomolecules completes at small intestine.

Carbohydrate digestion starts in mouth by the enzyme amylase present in the saliva. Food enters into the stomach where the complex protein is digested into the simple protein of dipeptides by pepsin. In small intestine food is further digested in the presence of pancreatic juice and bile. Dipeptides are converted into the amino acids by trypsin and lipids are emulsified and digested by lipase and bile.

Therefore, the correct answer is option C.