DNA Replication - Medical Science

Q1:

Which of the following lacks 3'-5' exonuclease activity?

A Short fragment of DNA polymerase I

B Taq DNA polymerase

C T4 DNA ligase

D All of the above

ANS:D - All of the above

Both DNA polymerase 1 and T4 DNA ligase possess 3'-5' exonuclease activityi .e, proofreading activity. So the correct answer is B.