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The Epic Interactive Encyclopedia 1998
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Epic Interactive Encyclopedia, The - 1998 Edition (1998)(Epic Marketing).iso
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Ageing
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INFOTEXT
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1992-09-02
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700b
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18 lines
In common usage, the period of deterioration
of the physical condition of a living
organism that leads to death; in biological
terms, the entire life process. Three current
theories attempt to account for ageing. The
first suggests that the process is
genetically determined, to remove individuals
that can no longer reproduce. The second
suggests that it is due to the accumulation
of mistakes during the replication of DNA at
cell division. The third suggests that it is
actively induced by pieces of DNA that move
between cells, or by cancer-causing viruses;
these may become abundant in old cells and
induce them to produce unwanted proteins or
interfere with the control functions of their
DNA.