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Name: Jazir
Status: Other
Grade:  Other
Location: N/A
Country: N/A
Date: August 2007


Question:
Why does RNA has uracil instead of thymine?



Replies:
The difference between thymine and uracil is a single methyl group in thymine that does not appear in uracil, in fact, the chemical name of thymine is 5-methyl uracil. This methyl group is located in a region of thymine that is not involved in Hydrogen bonding to adenine so it behaves just like uracil. The reason why DNA and RNA are different, only God knows!

Ron Baker, Ph.D.


The backbone of RNA is a ribose sugar rather than a deoxyribose sugar that identifies DNA. "Deoxy" refers to the fact that it is a ribose sugar missing an oxygen atom. It has been shown that thymine will not bond correctly with the ribose sugar backbone configuration. Uracil will and acts as a functional substitute. Guanine, cytosine and adenine will bond with either.

Since you have failed to identify your age. You will have to be happy with this explanation.

Steve Sample



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