apoptosis

apoptosis

 or programmed cell death

Mechanism that allows cells to self-destruct when stimulated by the appropriate trigger. It may be initiated when a cell is no longer needed, when a cell becomes a threat to the organism's health, or for other reasons. The aberrant inhibition or initiation of apoptosis contributes to many disease processes, including cancer. Though embryologists had long been familiar with the process of programmed cell death, not until 1972 was the mechanism's broader significance recognized. Apoptosis is distinguished from necrosis, a form of cell death that results from injury.

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apoptosis [‚ā·pō′tō·səs]

(cell and molecular biology)

Death of cells triggered by extracellular signals or genetically programmed events, carried out by processes within the cell, and characterized by systemic breakdown of cellular constituents, in particular chromosomal deoxyribonucleic acid; may be involved in normal development and aging, or may serve to eliminate defective or damaged cells. Also known as programmed cell death.