07-13-13, 12:54 PM
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#10
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Member
Join Date: Jan-2012
Posts: 636
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Re: Which snakes have the longest lifespans?
Quote:
Originally Posted by franks
Why does a slow metabolism translate to a longer life?
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If I am recalling correctly from my university biology courses, aging is the result of the accumulation of defects in chromosomal DNA. Each time cells undergo division, the possibility of a defect occurring is present. Damage to DNA also naturally occurs from a variety of other factors, as well. The more frequently a cell divides, the more likely a defect in DNA replication will occur. (Not unlike "shooting craps". The more often you toss the dice, the higher the likelihood of "crapping out".) If the cell's DNA is already damaged due to other factors -- such as exposure to UV light -- then not only is the possibility of a mistake in DNA transcription present, but in addition the damaged DNA will be replicated so now you have two cells with defects. Organisms with faster metabolisms undergo cell divisions more frequently. As a result, they accumulate DNA defects more quickly, and therefore age more quickly.
Did that make sense, Frank?
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