DNA polymerases in all organisms add only 5’ nucleotides to the 3’ end of a growing...

DNA polymerases in all organisms add only 5’ nucleotides to the 3’ end of a growing DNA strand, never to the 5’end. One possible reason for this is the fact that most DNA polymerases have a proofreading function that would not be possible if DNA synthesis occurred in the 3’-5’ direction.

a. Sketch the reaction that DNA polymerase would have to catalyze if DNA synthesis occurred in the 3’-5’ direction.

b. Consider the information in your sketch and speculate as to why proofreading would be problematic.

Expert Solution

Hence the answer

gladiator answered 1 year ago

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