Endocrine hormones are released by the thyroid, parathyroid, adrenal and other glands, under the general direction of the pituitary gland.
Hormones are:
one of the body's great communication networks (the others are the nervous and immune systems). A hormone molecule, released by one of about a dozen glands, travels through the blood until it reaches a cell with a receptor that it fits. Then, like a key in a lock, the molecule attaches to the receptor and sends a signal inside the cell. The signal may tell the cell to produce a certain protein or to multiply.
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Wanna know what these things do?
Hormones are involved in just about every biological process: immune function, reproduction, growth, even controlling other hormones. They can work at astonishingly small concentrations -- in parts per billion or trillion, which is one reason that small doses of endocrine disrupters could be so dangerous.
Teenagers aren't the only ones suffering hormonal chaos.
