the scientific study of the biological process of aging.

organisms that reproduce only once, usually followed by death, as observed in several animals

one of two or more variant forms of a gene.

inability to feed oneself due to anatomical deficiencies, common in the adult phase of some species of animals

programmed cell death.

theory

digestion of the cell's own components; it has been implicated in aging

diet regime consisting of eating considerably fewer calories, without malnutrition, that has been considered as a potential method to delay aging.

see replicative senescence.

the ability of certain cell populations, like most cancer cells, to divide indefinitely in culture.