Question

Proofreading activity of DNA polymerase improves fidelity of replication by a factor of _____ fold?

a) 100-500
b) Does not improve it at all.
c) 1000-5000
d) 10-100

Answer 1

The proofreading activity of DNA polymerase improves the fidelity of DNA replication by 100-500 fold by correcting mismatches through the exonuclease activity of the polymerase.

Step-by-step explanation:

The proofreading activity of DNA polymerase improves the fidelity of replication by a significant factor. Specifically, the proofreading process by DNA polymerase enhances the accuracy by which DNA is replicated by correcting mismatches that can occur as the polymerase adds nucleotides. When an incorrect nucleotide is added, the exonuclease activity of DNA polymerase removes the wrong nucleotide, allowing for the correct base to be added instead. This mechanism significantly reduces the number of replication errors, improving replication fidelity by 100-500 fold.