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Name: Bill S.
Status: Educator
Age: 30s
Location: N/A
Country: N/A
Date: 2002

Why did DNA and not RNA evolve to carry the genetic code in all organisms save a few viruses? Would the structure of RNA allow the formation of a stable double-stranded helix if two RNA chromatids were synthesized?

I am not 100% sure of the reason, but I remember hearing that the conformation of DNA makes it more stable than RNA. So it seems RNA came first, being able to replicate, but RNA is very unstable and breaks down quickly. Then to stabilize the information perhaps DNA evolved and then double-stranded DNA, with RNA then acting as the go between.


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