Polysaccharide of moving animals. Cellulose and chitin are examples of structural polysaccharides. Cellulose is used in the cell walls of plants and other organisms, and is said to be the most abundant organic molecule on Earth. It has many uses such as a significant role in the paper and textile industries, and is used as a feedstock for the production of rayon (via the viscose process), cellulose acetate, celluloid, and nitrocellulose. Chitin has a similar structure, but has nitrogen-containing side branches, increasing its strength. It is found in arthropod exoskeletons and in the cell walls of some fungi. It also has
Crustacean the zoea stage is followed by the mysis stage, and in others, by the megalopa stage, depending on the crustacean group involved. The name "crustacean" dates from the earliest works to describe the animals, including those of Pierre Belon and Guillaume Rondelet, but the name was not used by some later authors, including Carl Linnaeus, who included crustaceans among the "Aptera" in his '. The earliest nomenclaturally valid work to use the name "Crustacea" was Morten Thrane Brünnich's ' in 1772, although he also included chelicerates in the group. The subphylum Crustacea comprises almost 67,000 described species, which is thought