During DNA replication, the strands separate bya)DNA polymeraseb)Topoisomerasec)Unwindase/Helicased)GyraseCorrect answer is option 'C'. Can you explain this answer?

Question

Answer

Helicase is enzyme which uses energy and break the hydrogen bonds and create replication fork. and hence separate DNA strands.

Answer

DNA helicase is responsible for opening up our DNA to allow for replication as well as the transcription of our DNA . A DNA helicase is an enzyme that function by melting the hydrogen bonds that hold the DNA into the double helix structure .It is also know as Unwindase.
So,the correct option is Unwindase/Helicase.

Answer

Function of topoisomerase??

Answer

Helicase aur unwindase is an enzyme which is used to unwind a DNA strand. It breaks the hydrogen bonds between the two complementary strands of DNA thus creating a replication fork for the process of DNA replication

Answer

Explanation:

During DNA replication, the strands of the DNA molecule separate, allowing for the synthesis of two new strands. This process is carried out by a group of enzymes called helicases or unwindases.

Unwinding of DNA:
- Unwindase, also known as helicase, plays a crucial role in separating the DNA strands during replication. It binds to the origin of replication, which is a specific sequence of DNA, and uses ATP energy to break the hydrogen bonds between the base pairs.
- Helicase moves along the DNA molecule in a specific direction, unwinding the two strands and creating a replication fork.
- The unwinding of DNA by helicase creates tension and stress ahead of the replication fork, which can cause the DNA molecule to become supercoiled.
- To relieve this supercoiling, another enzyme called topoisomerase, specifically gyrase, acts by introducing temporary breaks in the DNA molecule and allowing it to rotate, thus decreasing the tension.

Other enzymes involved:
- DNA polymerase: Once the DNA strands are separated, DNA polymerase comes into play. It is responsible for synthesizing new DNA strands using the existing strands as templates.
- DNA polymerase adds nucleotides to the growing strand in a 5' to 3' direction, following the base-pairing rules (A with T, G with C).
- The leading strand is synthesized continuously in the same direction as the replication fork, while the lagging strand is synthesized discontinuously in short fragments called Okazaki fragments.
- DNA polymerase also has a proofreading function, which helps to maintain the accuracy of DNA replication by correcting any errors that occur during the synthesis.

Conclusion:
In summary, during DNA replication, the strands separate with the help of unwindase or helicase enzymes. These enzymes break the hydrogen bonds between the base pairs, allowing the DNA molecule to unwind and form a replication fork. Other enzymes such as topoisomerase and DNA polymerase are also involved in the process to relieve supercoiling and synthesize new DNA strands, respectively.

Similar NEET Doubts

During DNA replication, the strands separate by[1993]

During DNA replication, strand separation by breaking the H-bonds is performed by- (1)Topoisomerase (2)Gyras (3)Helicases (4)More than one option is correct Right ans (3) can u explain ?

During DNA replication in prokaryotes which DNA polymerase removes the RNA primer after replication on lagging strand?

Protein helping in opening of DNA double helix in form of replication fork is[1994]

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