Final answer:
Programmed cellular self-destruction is called apoptosis, a controlled biological process for a cell to die without releasing harmful substances, distinguished from accidental cell death (necrosis) and cell dormancy (senescence).
Step-by-step explanation:
The process of programmed cellular self-destruction is called apoptosis. This biological process allows a cell to die in a controlled manner that prevents the release of potentially damaging molecules from inside the cell. Cells may undergo apoptosis in response to various stimuli, including when they are damaged, superfluous, or potentially dangerous to an organism. There are many internal checkpoints that monitor a cell's health; if abnormalities are observed, or if a cell suffers physical damage or a debilitating somatic mutation, it may spontaneously initiate the process of apoptosis.
Importantly, this process is different from necrosis, which is accidental death caused by external injury, and from senescence, an irreversible state of dormancy. In cancer, the regulation of apoptosis can be disrupted, leading to unregulated cell division and tumor formation. The DNA repair ability of a cell is vital to maintaining this balance and facilitating apoptosis when needed.