Many other common diseases are caused by autoimmunity such as juvenile diabetes and low thyroid disease. It has been recently discovered that some persons who suffer with hives or angioedema also have an autoimmune disease. In these cases, autoantibodies have been formed that bind to the Fc-receptor on mast cells.
Lesson Summary. Chitin is a primary component in the exoskeletons of arthropods and crustaceans and is also found in the cell walls of fungi. It's a polysaccharide, and it's excreted by the epidermal cells in arthropods. But, it can't grow with the animal, so shedding becomes necessary.
Chitin is found in fungi cell walls. Some diatoms (a type of protazoa) contain chitin in their cell walls along with inorganic glass-like substances.hitin is found in the cell walls of fungi, the exoskeletons of arthropods such as crustaceans and insects, the radulae of molluscs, and the beaks and internal shells of cepha â¦ lopods, including squid and octopuses.