Cellulose is an insoluble and dead substance.The cell wall of plant cells are made out of it.
1.)It cannot by digested by the human digestive system,hence when we eat vegetables or fruits,the cellulose remains in its original condition and acts as a roughage in the digestive system.This helps us in the clearance of our bowels.TO avoid constipation,etc.
2.)It gives a rigid shape to the plant cells and the membrane which allows all the substances to enter into the plant cell.
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