Which of the following exonuclease activities is present in DNA polymerase I?
A)3' exonuclease that degrades double stranded DNA
B)3' exonuclease that degrades hairpin DNA
C)5' exonuclease that degrades single stranded DNA
D)5' exonuclease that removes RNA from a DNA-RNA duplex
E)none of the above

Question

Quizplus · Accepted Answer

DNA polymerase I has a 5' to 3' exonuclease activity that removes RNA primers from a DNA-RNA duplex during DNA replication. This activity is important for DNA polymerase I to replace RNA primers with DNA nucleotides. The other options listed do not describe known exonuclease activities of DNA polymerase I.

Which of the Following Exonuclease Activities Is Present in DNA