BIOMOLECULES AND ENZYMES

Detailed explanation-1: -Humans cannot digest cellulose because they lack the enzymes essential for breaking the beta-acetyl linkages. The undigested cellulose acts as fibre that aids in the functioning of the intestinal tract.

Detailed explanation-2: -Solution 7: Cellulose (a type of carbohydrate) can be digested by ruminants but not by humans because ruminants have a large sac-like structure called rumen between the oesophagus and the small intestine. The cellulose of the food is digested here by the action of certain bacteria which are not present in humans.

Detailed explanation-3: -Carnivorous animals cannot digest cellulose, hence they have a shorter intestine.

Detailed explanation-4: -Hay and grasses are particularly abundant in cellulose, and both are indigestible by humans (although humans can digest starch). Animals such as termites and herbivores such as cows, koalas and horses all digest cellulose, but even these animals do not themselves have an enzyme that digests this material.

Detailed explanation-5: -Cellulose is a type of fiber that cannot be digested by the human digestive system.