apoptosis

Main Entry: apop·to·sis
Pronunciation: "ap-&(p)-'tO-sis, -äp-, -O-; "A-päp-
Function: noun
: a genetically determined process ofcell self-destruction that is marked by the fragmentation of nuclear DNA, is activated either by the presence of a stimulus or by the removal of a stimulus or suppressing agent, is a normalphysiological process eliminating DNA-damaged, superfluous, or unwanted cells (as immune cells targeted against the self in the development of self-tolerance or larval cells in amphibians undergoingmetamorphosis), and when halted (as by genetic mutation) may result in uncontrolled cell growth and tumor formationcalled also programmed cell death —apop·tot·ic /-'tät-ik/ adjective

apoptosis   (āp'əp-tō'sĭs, āp'ə-tō'-)  Pronunciation Key  A natural process of self-destruction in certain cells, such as epithelial cells and erythrocytes, that are genetically programmed to have a limited life span or are damaged. Apoptosis can be induced either by a stimulus, such as irradiation or toxic drugs, or by removal of a repressor agent. The cells disintegrate into membrane-bound particles that are then eliminated by phagocytosis. Also called programmed cell death.