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chitin vs. cellulose

[kahy-tin] / ˈkaɪ tɪn /

noun

Biochemistry.
  1. a nitrogen-containing polysaccharide, related chemically to cellulose, that forms a semitransparent horny substance and is a principal constituent of the exoskeleton, or outer covering, of insects, crustaceans, and arachnids.

[sel-yuh-lohs] / ˈsɛl yəˌloʊs /

noun

  1. an inert carbohydrate, (C 6 H 10 O5 ) n, the chief constituent of the cell walls of plants and of wood, cotton, hemp, paper, etc.