Question

draw the digestive system of human being and cable the part we cannot digest cellulose like the course why
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Answer 1

• Humans are unable to digest cellulose because of the absence of appropriate enzymes (cellulose) to break down the beta acetal linkages. Undigestible cellulose is the fiber which aids in the smooth working of the intestinal tract.

• Besides, human beings are omnivores. They do not necessarily feed on grass and other plant material. Therefore, there is a very minimal need for digesting cellulose as compared to ruminants.

Answer 2

Food is stored in the plants as cellulose. Cellulase is an enzyme synthesized by bacteria in stomach of ruminant which is used to digest cellulose. Humans do not have cellulase and hence they cannot digest cellulose.

So, the correct answer is 'They do not have cellulose-digesting bacteria on their stomach'.