Question

Initiation of DNA strand synthesis is performed by

• A. DNA polymerase I
• B. DNA Helicase
• C. DNA Primase
• D. DNA Topoisomerase

Answer 1

The correct option is B DNA Helicase

During DNA replication, the double helix unwinds as the preliminary step. The unwinding of DNA strand is catalyzed by helicase enzyme.Helicases move along the double-stranded DNA and separate the strands by breaking hydrogen bonds at the expense of energy from ATP. The single strands thus formed allow each strand to be copied. DNA unwinding by helicases creates topological stress in the helical DNA structure which is relieved by the action of topoisomerases.

Thus, the correct answer is option B.