DNA Replication - Medical Science

Q1:

Which of the following possesses both 5'-3' and 3'-5' exonuclease activity?

A Kornberg enzyme

B DNA polymerase III

C Taq DNA polymerase

D None of these

ANS:A - Kornberg enzyme

DNA pol 1.

5' to 3' exonuclease --> removal of primer.
5' to 3' polymerization ----> add nucleotides in place of primer(removed).
3' to 5'exonculease----> proofreading of this newly synthesized segment.