Death
Death is the termination of life in a living system, or in part thereof. It
can be considered the opposite of birth.
Biologically, death can occur to wholes, to parts of wholes, or to both. For
example, it is possible for individual cells and even organs to die, and yet
for the organism as a whole to continue to live; many individual cells can
live for only a short time, and so most of an organism's cells are
continually dying and being replaced by new ones.
Conversely it is also possible for the organism to die and for cells and
organs to live and to be used for transplantation. In the latter case,
though, the still-living tissues must be removed and transplanted quickly or
they too will soon die without the support of their host.
Irreversibility is often cited as a key feature of death and, indeed,
scientists have not been able to watch a living organism die and later bring
it back to life. Nonetheless, many people do not seem convinced that death
is always and necessarily irreversible; thus some have a literal belief in
the resurrection of Jesus Christ, while others have high hopes for the
eventual prospects of Cryonics.
Human Death: Definitions and Significance
By far the most important sort of death to most human beings is human death.
Thinking about human death raises a number of questions.
First, how can we identify the exact moment at which death has occurred?
This seems important, because identifying that moment would allow us to put
the correct time on death certificates, make sure that the deceased's will
is enacted only after the deceased is truly deceased, and in general guide
us regarding when to act as one should act toward a living person and when
to act as one should toward a dead person. In particular, identifying the
moment of death is important in cases of organ transplant, as organs must be
harvested as quickly as possible after death.
Historically, attempts to define the exact moment of death have been
problematic. Death was once defined as the cessation of heartbeat and
breathing, for example, but the development of CPR and early defibrillation
posed a challenge: either the definition of death was incorrect, or
techniques had been discovered that really allowed one to reverse death
(because, in some cases, breathing and heartbeat can be restarted).
Generally, the first option was chosen. (Today this definition of death is
known as "clinical death".)
Today, where a definition of the moment of death is required, we usually
turn to "brain death" or "biological death": people are considered dead when
the electrical activity in their brain ceases. It is presumed that a
stoppage of electrical activity indicates the end of consciousness. Those
that view that only the neo-cortex of the brain is necessary for
consciousness, however, sometimes argue that only electrical activity there
should be considered when defining death. In most places the more
conservative definition of death (cessation of electrical activity in the
whole brain, as opposed to just in the neo-cortex) has been adopted (for
example the Uniform Definition of Death Act in the United States).
Even in these cases, the determination of death can be difficult. EEGs can
detect spurious electrical impulses when none exists, while there have been
cases in which electrical activity in a living brain has been too low for
EEGs to detect. Because of this, hospitals often have elaborate protocols
for determining death involving EEGs at widely separated intervals.
It might also be worthwhile to entertain the possibility that death does not
occur at a particular moment, but unfolds as a process over a period of
time. Perhaps, in the end, it is not terribly meaningful to speak of "the
exact moment of death".
What happens to humans after death?
Second, and more interesting to many, what, if anything, happens to the
human spirit, consciousness or soul when they die? Is there perhaps an
afterlife? Can we expect reincarnation? These questions are of long
standing. For many, believe in an afterlife is a consolation in connection
with death of a beloved one or the prospect of one's own death. On the other
hand, fear of hell etc. may make death worse. Human contemplation about
death is an important motivation for the development of organized religion.
Many anthropologists feel that the careful burials among Neanderthals, where
ornamented bodies were laid in carefully dug, flower-strewn graves, is
evidence of early belief in an afterlife.
Physiological consequences of human death
For the human body, the physiological consequences of death include rigor
mortis, algor mortis, livor mortis (dependent lividity) and decomposition (decay).
The deceased person is usually either cremated or deposited in a tomb, often
a hole in the earth, called a grave. This happens during or after a funeral ceremony.
Graves are usually grouped together in a plot of land called a "cemetery" or
a "graveyard" and are often arranged by a funeral home or undertaker.
Quote (Peter Pan): To die will be an awfully big adventure.
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Death is also a popular mythological figure who has existed in mythology and
popular culture since the earliest days of storytelling. The traditional
image of Death is also a tarot card.
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