Chitin and Cellulose are both structural molecules.
Cellulose is the principal support and strength of plants and trees because it is the main component of its cell walls. It is the most abundant natural polymer on earth. It is a long chain of linked sugar molecule with a formula of (C6H10O5)n. It has Beta(1,4) linkages and its strands form extended ribbons.
Chitin also serves almost the same function as the cellulose. But it serves as the exoskeleton of crustaceans, insects, spiders, and cell walls of fungi. It formula is (C8H13O5N)n. It uses N-acetyl glucosamine in its structures unlike the glucose found in the structure of the cellulose.
Strands of cellulose are parallel. Strands of Chitin are either parallel or nonparallel.
