EVERYDAY SCIENCE

Detailed explanation-1: -The Anterior Pituitary. The anterior pituitary produces several important hormones that either stimulate target glands (e.g., the adrenal glands, gonads, or thyroid gland) to produce target gland hormones or directly affect target organs.

Detailed explanation-2: -A target cell responds to a hormone because it bears receptors for the hormone. In other words, a particular cell is a target cell for a hormone if it contains functional receptors for that hormone, and cells which do not have such a receptor cannot be influenced directly by that hormone.

Detailed explanation-3: -Paracrine, autocrine and synaptic are three types of local hormone signaling. In paracrine signaling, hormones are released into the fluid between cells (the interstitial fluid) and diffuse to nearby target cells.

Detailed explanation-4: -So why do hormones affect only their target cells in particular tissues? Because only those target cells have receptors for that particular hormone. Some hormones bind to receptors on the surface of target cells. Others enter the cells and bind to receptors in the cytoplasm or nucleus.

Detailed explanation-5: -Hormones act as chemical messengers that are released into the blood stream to act on an organ in another part of the body. Although hormones reach all parts of the body, only target cells with compatible receptors are equipped to respond.