Delete Content. A plasma membrane is permeable to specific molecules that a cell needs. Transport proteins in the cell membrane allow for selective passage of specific molecules from the external environment. Each transport protein is specific to a certian molecule (indicated by matching colors).
The pancreas contains cells which release both insulin and glucagon. The endocrine system consists of a number of different glands which secrete hormones that dictate how cells and organs behave.
Polyuria (excessive urine) and polydipsia (excessive thirst) occur in diabetes mellitus as a reaction to high blood sugar. Type 1 diabetes occurs when the pancreas stops or nearly stops producing the hormone insulin.