Question

What enzyme is responsible for DNA replication?

Select one:

a. RNA polymerase

b. DNA ligase

c. EcoR1

d. DNA polymerase

e. Reverse transcriptase

Answer 1

d. DNA polymerase. DNA polymerase is the enzyme that is involved in the synthesis of DNA from its nucleotides and is crucial for DNA replication. It requires free 3'OH and synthesizes DNA with a directionality that is reverse of the direction of its movement.

RNA polymerase is the enzyme involved in transcription, i.e. the synthesis of RNA from DNA, Reverse transcriptase is the viral enzyme found in RNA viruses that synthesizes DNA from the RNA genetic material found in those viruses. DNA ligase is involved in ligation or joining of DNA where there was a nick or a cut. EcoRI is a restriction endonuclease obtained first from E.coli and cleaves at the recognition sequence G/AATTC.