Death
Death is the end of an organism's life. It is the irreversible cessation of biological functions that sustain a living organism. Entropy, nature's tendency toward disorder, can contribute to the breakdown of living systems over time. Upon death, organisms stop exhibiting behavior and generally begin to decompose through various physical and chemical processes. Death can occur at any stage of development, including in infancy. A person may experience clinical death that is reversible, resulting in some cases in a near-death experience. In humans, establishing death of the brain determines that an individual has irreversibly died.
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