Looking for classes? Ksquare Career Institute, Bengaluru →
Which one of the following pairs of food components in humans reaches the stomach totally undigested?
A
Starch and cellulose
B
Protein and starch
C
Starch and fat
D
Fat and cellulose
Detailed Solution
The only chemical digestion that takes place before food reaches the stomach is in the buccal cavity.
Saliva contains salivary amylase, which hydrolyses about 30 per cent of starch into maltose at pH 6.8. So starch does not reach the stomach totally undigested.
Saliva has no protein-digesting enzyme and no effective fat-digesting enzyme, so proteins and fats reach the stomach undigested.
Cellulose is not digested anywhere in the human gut, since humans have no cellulase.
Among the given pairs, the one in which both components reach the stomach totally undigested is fat and cellulose.
Saliva contains salivary amylase, which hydrolyses about 30 per cent of starch into maltose at pH 6.8. So starch does not reach the stomach totally undigested.
Saliva has no protein-digesting enzyme and no effective fat-digesting enzyme, so proteins and fats reach the stomach undigested.
Cellulose is not digested anywhere in the human gut, since humans have no cellulase.
Among the given pairs, the one in which both components reach the stomach totally undigested is fat and cellulose.