The enzyme responsible for proofreading a growing DNA strand and for replacing mismatched nucleotides is:
A)DNA polymerase.
B)helicase.
C)topoisomerase II.
D)DNA ligase.
E)DNA replicase.

Question

Quizplus · Accepted Answer

DNA polymerase is responsible for proofreading a growing DNA strand and correcting mistakes in nucleotide pairing. This process is called exonuclease proofreading. Helicase unwinds and separates the double-stranded DNA molecule. Topoisomerase II helps relieve the twisting and strain on the DNA molecule during replication. DNA ligase seals the gaps between the newly replicated fragments of DNA. DNA replicase is not an enzyme and is not involved in proofreading or repairing DNA.

The Enzyme Responsible for Proofreading a Growing DNA Strand and for Replacing