Definition of chitin
a complex polysaccharide, a polymer of N-acetylglucosamine, found in the exoskeletons of arthropods and in the cell walls of fungi; thought to be responsible for some forms of asthma in humans
Examples of chitin in the following topics:
- Arthropods also show the presence of an exoskeleton made principally of chitin, which is a waterproof, tough polysaccharide.
- It is made up of two layers: the epicuticle, which is a thin, waxy, water-resistant outer layer containing no chitin; and the chitinous procuticle, which is beneath the epicuticle.
- Chitin is a tough, flexible polysaccharide.
- Arthropods are the largest grouping of animals all of which have jointed legs and an exoskeleton made of chitin.
- Like all fungi, chytrids have chitin in their cell walls, but one group of chytrids has both cellulose and chitin in the cell wall.
- As the tough and resistant outer cover of an arthropod, the exoskeleton may be constructed of a tough polymer, such as chitin, and is often biomineralized with materials, such as calcium carbonate.
- The increasing thickness of the chitin necessary to support this weight limits most animals with an exoskeleton to a relatively-small size.
- Arthropods, such as crabs and lobsters, have exoskeletons that consist of 30–50 percent chitin, a polysaccharide derivative of glucose that is a strong-but-flexible material.
- Chitin is secreted by the epidermal cells.
- Starch, glycogen, cellulose, and chitin are primary examples of polysaccharides.
- This exoskeleton is made of chitin, which is a polysaccharide-containing nitrogen.
- Chitin is also a major component of fungal cell walls.
- The rigid layers of fungal cell walls contain complex polysaccharides called chitin and glucans.
- Chitin, also found in the exoskeleton of insects, gives structural strength to the cell walls of fungi.
- The tracheal system, the most direct and efficient respiratory system in active animals, has tubes made of a polymeric material called chitin.
- The cuticle of Nematodes is rich in collagen and a carbohydrate-protein polymer called chitin.
- The composition of their cell walls also differs from the eukaryotic cell walls found in plants (cellulose) or fungi and insects (chitin).