Estimates of mutation rates for a variety of genes indicate that the frequency of errors during replication is much lower than would be predicted on the basis of complementary base pairing. What accounts for the higher degree of fidelity?
A) Conformational changes in DNA polymerase
B) 3ʹ to 5ʹ exonuclease activity of DNA polymerase
C) Requirement of a primer for DNA synthesis by DNA polymerase
D) All of the above

Question

Quizplus · Accepted Answer

All of the options listed contribute to the high fidelity of DNA replication. Conformational changes in DNA polymerase help ensure correct base pairing, 3ʹ to 5ʹ exonuclease activity allows for the correction of mistakes by removing mismatched bases, and the requirement of a primer ensures that DNA polymerase only adds nucleotides to an existing strand, reducing errors.

Estimates of Mutation Rates for a Variety of Genes Indicate