Plants contains cellulose and humans cannot digest it.Then how can human absorb the nutrients present inside the cellulose of a green leafy vegetable?
Answers
Answer:
Cellulose is a complex organic compound that occurs abundantly in nature. It is a polymeric carbohydrate molecule consisting of a linear chain having thousands of glycosidic linkages.
It consists of unbranched chains of glucose (linked D-Glucopyranose). They are straight chains linked by hydrogen bonds producing a substance that is inert and insoluble in water, in their pure form.
Modified cellulose and pure cellulose are different in their chemical compositions. They are components of the plant cell wall and have no odour or taste. It is crystalline in nature and does not dissolve water and other solvents. Termites and herbivorous animals lack the enzyme for cellulose digestion.
Cellulose is a fibre which is not digestible by the human digestive system. It, however, helps in the smooth functioning of the intestinal tract.
The presence of beta acetal linkages in cellulose makes it different from starch and is a deciding factor in its digestibility. Humans lack the enzyme required to breakdown the linkages. Furthermore, it forms a major part of the human diet from plant foods.
Fruits and vegetables contain cellulose in small amounts which are easily digestible. Fibres contain cellulose which acts as roughage, adding bulk to consumed food and helps in the smooth passage of the food efficiently and at a much faster pace. High fibre diet reduces the risk of colon cancer as fibre in the diet helps reduce the time the faeces stay in the colon wall.
Since it is insoluble in water it binds with other components adding bulk helping to move through the intestines by aiding bowel movements. Consuming food that does not contain cellulose over a period of time results in the bowel becoming weak leading to constipation.
These fibres aid in the growth of bacteria in the gut which feeds on sugars and fibres. They maintain the health of the gut and checks for bacteria causing illness. Fibres also prevent weight gain and aids in weight loss.
humans are unable to digest cellulose because the appropriate enzymes to breakdown the beta acetal linkages are lacking. ... Undigestible cellulose is the fiber which aids in the smooth working of the intestinal tract. Animals such as cows, horses, sheep, goats, and termites have symbiotic bacteria in the intestinal tract.