Sometimes friction on the skin--from clothing, for example--will cause a hair follicle to swell up. This can make the opening close up, trapping the bacteria inside and starting an infection. Boils and carbuncles often form in moist areas of the body such as the back of the neck, buttocks, thighs, groin, and armpits. If you have a chronic illness, such as diabetes or kidney or liver disease, you may be more likely to have boils and carbuncles.
Islets of Langerhans. The islets of Langerhans are the endocrine (endo= within) cells of the pancreas that produce and secrete hormones such as insulin and glucagon into the bloodstream. The pancreatic hormones, insulin and glucagon, work together to maintain the proper level of sugar (glucose) in the blood. Blood sugar is used by the body for energy. An understanding of the two functional components of the pancreas is important for two reasons.
The pancreas has two main functions. It produces substances called enzymes that aid in the digestion of fats, carbohydrates and proteins. It also produces hormones that regulate different functions of the body. The two main hormones produced by the pancreas are insulin and glucagon. Insulin lowers blood sugar levels while glucagon raises blood sugar levels. These two hormones work together to maintain the proper level of sugar in the blood.