Kids Research Express

Insulin, hormone , produced in the islets of Langerhans of the pancreas , that regulates the metabolism of carbohydrates, fats, and starches in the body. Like other proteins, insulin is partially digested if administered orally and hence must be injected into a muscle when used clinically. In the treatment of diabetes mellitus , which is caused by a deficiency of insulin production or by inhibition of its action on cells, insulin is often combined with protamine, which prolongs the period of absorption of the hormone. Insulin crystallized from the pancreas contains zinc, which also lengthens absorption. A preparation called protamine zinc insulin extends the hormone's action still further. Insulin was first extracted from the pancreatic tissue of dogs in 1921 by the Canadian physiologists Sir Frederick Grant Banting and Charles Herbert Best and the British physiologist John James Rickard Macleod. The Canadian biochemist James Bertram Collip then produced it in sufficiently pure for...

Hormone, chemical that transfers information and instructions between cells in animals and plants. Often described as the body’s chemical messengers, hormones regulate growth and development, control the function of various tissues, support reproductive functions, and regulate metabolism (the process used to break down food to create energy). Unlike information sent by the nervous system , which is transmitted via electronic impulses that travel quickly and have an almost immediate and short-term effect, hormones act more slowly, and their effects typically are maintained over a longer period of time. Hormones are made by specialized glands or tissues that manufacture and secrete these chemicals as the body needs them. The majority of hormones are produced by the glands of the endocrine system , such as the pituitary , thyroid , adrenal glands , and the ovaries or testes . These endocrine glands produce and secrete hormones directly into the bloodstream. However, not all hormones are...