Question

During DNA replication the strands separate by
A. DNA polymerase
B. Topoisomerase
C. Unwindase/ helicase
D. Gyrase

Answer 1

Hint: DNA is a self-replicating structure that replicates semi-conservatively, as we know. DNA replication, on the other hand, is aided by a series of enzymes.
DNA replication is the process through which DNA generates multiple copies of itself. It's a three-stage biological polymerization process that includes initiation, elongation, and termination. It's a reaction that's catalysed by enzymes. The most critical enzyme in the replication process is DNA polymerase.

Complete answer:
Option A: DNA polymerase is an enzyme that converts deoxyribonucleotides (DNA's building blocks) into DNA molecules. The enzymes are needed for DNA replication and team together to make two identical DNA strands from a single DNA molecule.
So option A is not correct.
Option B: Topoisomerases (also known as DNA topoisomerases) are enzymes involved in the over- or underwinding of DNA. Topoisomerases bind to DNA and cleave the phosphate backbone of one or both DNA strands to prevent and rectify various types of topological defects produced by the double helix.
So option B is not correct.
Option C: The DNA helicase is important for opening up our DNA so that it may be replicated and transcribed. A DNA helicase is an enzyme that melts the hydrogen bonds that hold DNA together in its double helix form. 'Unwindase' is another name for it.
So option C is correct.
Option D: DNA gyrase is an ATP-dependent bacterial enzyme that catalyses the negative supercoiling of double-stranded closed-circular DNA. Gyrase is a member of the topoisomerase family of enzymes, which are involved in the regulation of DNA topological transitions.
So option D is not correct.

So option C is the correct answer.

Note:
Steps of DNA replication-
DNA helicase unwinds double strands of DNA, which leads to the creation of a replication fork at the origin. The enzyme primase is in charge of making RNA primers.
DNA polymerase polymerizes nucleotides in an orientation with complementary base pairing. One strand is reproduced continually, referred to as the leading strand, while the other is replicated infrequently, referred to as the lagging strand.
Replication forks terminate at various sites because DNA replication happens at multiple points at the same time. DNA ligase joins Okazaki fragments that have been produced in a random order.