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Discuss the double helix structure of DNA

Discuss the double helix structure of DNA.

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Cyril
-DNA is a double stranded helix with the two strands connected by hydrogen bonds.A bases are always paired with Ts and Cs are always paired with Gs,which is consistent with and accounts for Chargaffs rule.
-Most DNA double helices are right handed, that is if you were to hold your right hand out,with your thumb pointed up and your fingers curled around your thumb,your thumb would represent the axis of the helix and your fingers would represent the sugar phosphate backbone.Only one type of DNA,called Z-DNA is left handed.
-The DNA double helix is anti-parallel which means that the 5'end paired With 3'end of its complementary strands .Nucleotides are linked to each other by their phosphate groups which bind the 3' end of one sugar to the 5'end of the next.

Not only are the DNA base pairs connected via hydrogen bonding but the outer edges of the nitrogen containing bases are exposed and available for potential hydrogen bonding as well.These hydrogen bonds provide easy access to the DNA for other molecules including the proteins that play vital roles in replication and expression of DNA
patmalone254 answered the question on October 23, 2018 at 19:39

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