GENERAL HISTOLOGY

Detailed explanation-1: -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-2: -Hormones can be thought of as chemical messages. From the blood stream, the hormones communicate with the body by heading towards their target cell to bring about a particular change or effect to that cell. The hormone can also create changes in the cells of surrounding tissues (paracrine effect).

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: -Target cells are cells that are receptive to a secreted hormone. dependent on three factors; the hormone levels in the blood, the receptor levels on the target cell, and hormone–receptor affinity.

Detailed explanation-5: -Hormones bring about their characteristic effects on target cells by modifying cellular activity. Protein hormones react with receptors on the surface of the cell, and the sequence of events that results in hormone action is relatively rapid. Steroid hormones typically react with receptor sites inside a cell.