noun \ˌa-pəp-ˈtō-səs, -pə-ˈtō-\
plural ap·o·pto·ses \-ˌsēz\

Definition of APOPTOSIS

: a genetically determined process of cell 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 normal physiological 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 undergoing metamorphosis), and when halted (as by genetic mutation) may result in uncontrolled cell growth and tumor formation—called also programmed cell death
ap·o·pto·tic \-ˈtät-ik\ adjective

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