Death / Disease
Death is the termination of all biological functions that sustain a living organism.
Phenomena which commonly bring about death include biological aging (senescence), predation, malnutrition, disease, suicide, homicide, starvation, dehydration, and accidents or trauma resulting in terminal injury. Bodies of living organisms begin to decompose shortly after death. Death has commonly been considered a sad or unpleasant occasion, due to the termination of bonds with or affection for the being that has died, or having fear of death, necrophobia, anxiety, sorrow, grief, emotional pain, depression, sympathy, compassion, solitude, or saudade.
The word death comes from Old English deað, which in turn comes from Proto-Germanic *dauthuz (reconstructed by etymological analysis). This comes from the Proto-Indo-European stem *dheu- meaning the "Process, act, condition of dying".
The concept and symptoms of death, and varying degrees of delicacy used in discussion in public forums, have generated numerous scientific, legal, and socially acceptable terms or euphemisms for death. When a person has died, it is also said they have passed away, passed on, expired, or are gone, among numerous other socially accepted, religiously specific, slang, and irreverent terms. Bereft of life, the dead person is then a corpse, cadaver, a body, a set of remains, and when all flesh has rotted away, a skeleton. The terms carrion and carcass can also be used, though these more often connote the remains of non-human animals. As a polite reference to a dead person, it has become common practice to use the participle form of "decease", as in the deceased; the noun form is decedent. The ashes left after a cremation are sometimes referred to by the neologism cremains, a portmanteau of "cremation" and "remains".
Almost all animals who survive external hazards to their biological functioning eventually die from biological aging, known in life sciences as “senescence”. Some organisms experience negligible senescence, even exhibiting biological immortality. These include the jellyfish Turritopsis dohrnii, the hydra, and the planarian. Unnatural causes of death include suicide and homicide. From all causes, roughly 150,000 people die around the world each day. Of these, two thirds die directly or indirectly due to senescence, but in industrialized countries—such as the United States, the United Kingdom, and Germany—the rate approaches 90%, i.e., nearly nine out of ten of all deaths are related to senescence.
Physiological death is now seen as a process, more than an event: conditions once considered indicative of death are now reversible. Where in the process a dividing line is drawn between life and death depends on factors beyond the presence or absence of vital signs. In general, clinical death is neither necessary nor sufficient for a determination of legal death. A patient with working heart and lungs determined to be brain dead can be pronounced legally dead without clinical death occurring. As scientific knowledge and medicine advance, a precise medical definition of death becomes more problematic.
Signs of biological death
- Signs of death or strong indications that a warm-blooded animal is no longer alive are:
- Cessation of breathing
- Cardiac arrest (no pulse)
- Pallor mortis, paleness which happens in the 15–120 minutes after death
- Livor mortis, a settling of the blood in the lower (dependent) portion of the body
- Algor mortis, the reduction in body temperature following death. This is generally a steady decline until matching ambient temperature
- Rigor mortis, the limbs of the corpse become stiff (Latin rigor) and difficult to move or manipulate
- Decomposition, the reduction into simpler forms of matter, accompanied by a strong, unpleasant odor.