secretion

1. Production by a cell or aggregation of cells (a gland) of a physiologically active substance and its movement out of the cell or organ in which it is formed. 2. The solid, liquid, or gaseous product of cellular or glandular activity that is stored in or used by the organism in which it is produced. Cf.:excretion. [L. secerno, pp. -cretus, to separate]

- cytocrine s. the transfer of secretory material from one cell to another, such as the transfer of melanin granules from melanocytes to epidermal cells.

- external s. a substance formed by a cell and transported outside the cell walls as a means of ridding the cell of the substance or as a messenger to affect the function of other cells.

- neurohumoral s. transmission of a nerve impulse across a synapse or to an end-organ by s. of a minute amount of a chemical transmitter such as acetylcholine.

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se·cre·tion si-'krē-shən n

1) the process of segregating, elaborating, and releasing some material either functionally specialized (as saliva) or isolated for excretion (as urine)

2) a product of secretion formed by an animal or plant esp one performing a specific useful function in the organism

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n.

1. the process by which a gland isolates constituents of the blood or tissue fluid and chemically alters them to produce a substance that it discharges for use by the body or excretes. Principal methods of secretion - apocrine, holocrine, and merocrine.

2. the substance that is produced by a gland.

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se·cre·tion (se-kreґshən) [L. secretio, from secernere to secrete] 1. the process of elaborating a specific product as a result of the activity of a gland; this activity may range from separating a specific substance of the blood to the elaboration of a new chemical substance. 2. material that is secreted.