I'm insulin resistant, a type two diabetic, meaning I have larage amounts of sugar in my bloodstream. Over time, these large amounts of sugar wreak havoc on the body and/or various organs. The build up of sugar in the blood can cause an increase in urination (to try to clear the sugar from the body). When the kidneys lose the glucose through the urine, a large amount of water is also lost, causing dehydration (which might explain a lot with me at the moment). Insulin is needed to control blood sugar.
After glucose (blood sugar) rises above a certain level, insulin, which is a hormone) is released into the bloodstream, which allows cells to receive/use glucose for energy. Insulin is produced by the pancreas, specifically by the beta cells which make and release insulin. Beta cells are located in the Islet of Langerhands, which are groups of endocrine cells that constitue about 1-2% of the total mass of the pancreas. Each islet contains about a thousand cells. 65-90% of these cells are beta cells.
endocrine system notes: http://en.wikipedia.org/wiki/Endocrine
Diagram of pancreas. No, I have no idea why it looks like a winged penis:
