Insulin Insulin Insulin (from Latin "insula", island) is a peptide hormone produced by beta cells of the pancreatic islets; it is considered to be the main anabolic hormone of the body. It regulates the metabolism of carbohydrates, fats and protein by promoting the absorption of carbohydrates, especially glucose from the blood into liver, fat and skeletal muscle cells. In these tissues the absorbed glucose is converted into either glycogen via glycogenesis or fats (triglycerides) via lipogenesis, or, in the case of the liver, into both. Glucose production and secretion by the liver is strongly inhibited by high concentrations of insulin in
Uropygial gland nine families of birds lack a uropygial gland, mostly the ones unable to fly or the ones that produce powder down for feather maintenance. These include kiwis ("Apterygidae"), emu ("Dromaiidae"), ostriches ("Struthionidae"), rheas ("Rheidae"), cassowaries ("Casuariidae"), mesites ("Mesitornithidae"), bustards ("Otididae"), pigeons and doves ("Columbidae"), amazon parrots ("Psittacidae"), frogmouths ("Podargidae"), and woodpeckers ("Picidae"). These birds typically find other means to stay clean and dry, such as taking a dust bath. Researchers have been unable to correlate the presence or absence of the uropygial gland with factors such as distribution, climate, ecology, or flightlessness. The uropygial gland secretes an oil (preen oil)