Question

Which molecule is active first during DNA replication? A. Adenine B. Helicase enzyme C. DNA ligase D. DNA polymerase

Answer 1

Helicase. It unwinds and breaks the hydrogen bonds so other molecules can move on to the DNA strand and begin replication.

Answer 2

Answer: The correct answer is- B. Helicase enzyme.

DNA replication is a biological process of formation of two identical copies of DNA from a single original DNA molecule. Helicase or DNA helicase is an enzyme that is activated first ( in the intitiation phase of DNA replication).

This enzyme acts like a zipper as it unwinds ( unzip) the two strands of DNA so that template strands are exposed, which allows DNA polymerase enzyme to add nucleotides according to Watson and Crick base pairing.

Thus, B. Helicase enzyme is the right answer.