Death. Death is the permanent cessation of all biological functions that sustain a living organism.
   Phenomena which commonly bring about death include aging, predation, malnutrition, disease, suicide, homicide, starvation, dehydration, and accidents or major trauma resulting in terminal injury. In most cases, bodies of living organisms begin to decompose shortly after death.
   Death-particularly the death of humans-has commonly been considered a sad or unpleasant occasion, due to the affection for the being that has died and the termination of social and familial bonds with the deceased. Other concerns include fear of death, necrophobia, anxiety, sorrow, grief, emotional pain, depression, sympathy, compassion, solitude, or saudade.
   Many cultures and religions have the idea of an afterlife, and also hold the idea of reward or judgement and punishment for past sin. Senescence refers to a scenario when a living being is able to survive all calamities, but eventually dies due to causes relating to old age.
   Animal and plant cells normally reproduce and function during the whole period of natural existence, but the aging process derives from deterioration of cellular activity and ruination of regular functioning. Aptitude of cells for gradual deterioration and mortality means that cells are naturally sentenced to stable and long-term loss of living capacities, even despite continuing metaboli
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