Trev777
Junior Member (Idle past 5453 days) Posts: 14 From: N. Ireland Joined: 05-03-2009
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Message 91 of 151 (508004)
05-09-2009 5:25 PM
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Reply to: Message 87 by Fallen 05-06-2009 4:45 PM
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The first cell
The instructions within the DNA of a sigle cell, written out would fill a thousand 600 page books (Gore 1976). Advancements in science in this area have made it more not less, difficult to believe that all life on earth arose by chance. Francis Crick (Nobel Prize for discovering structure of DNA) stated, -"To produce this miracle of molecular construction all the cell need do is to string together the amino acids (which make up the polypeptide chain) in the correct order..Here we need only ask, how many posible proteins are there? If a particular amino acid sequence was selected by chance, how rare an event that would be? This is an easy exercise in combinatorials. Suppose the chain is about 200 amino acids long, this is if anything, rather less than the average length of proteins of all types. Since we have just twenty possibilities at each place, the number of possibilities is 20 multiplied by itself some 200 times. This is conveniently written 200 followed by 260 zeros.. Moreover we have only considered a polypeptide chain of a rather modest length. had we considered longer ones as well the figure would have been even more immense.
This message is a reply to: | | Message 87 by Fallen, posted 05-06-2009 4:45 PM | | Fallen has not replied |
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