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The endocrine system is made up of a network of glands. These glands secrete hormones to regulate many bodily functions, including growth and metabolism. Endocrine diseases are common and usually occur when glands produce an incorrect amount of hormones.
The endocrine system is a control system of ductless glands that secrete hormones within specific organs. Hormones act as messengers, and are carried by the bloodstream to different cells in the body, which interpret these messages and act on them. hormone is a chemical messenger produced by a cell that effects specific change in the cellular activity of other cells (target cells). Unlike exocrine glands (which produce substances such as saliva, milk, stomach acid and digestive enzymes), endocrine glands do not secrete substances into ducts (tubes).