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D Nitrogen-containing polysaccharide
Chitin is a nitrogen-containing polysaccharide that constitutes the cell wall of fungi and exoskeleton of arthropods. Chemically chitin is a polymer of N- acetylglucosamine. Amines are generally nitrogen containing compounds.
Chitin contains neither phosphorus nor sulphur. Chitin is not a simple polysaccharide.
Structure of chitin