THE MOLECULAR BASIS OF INHERITANCE
DNA REPLICATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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catalyzes the breaking of hydrogen bonds between base pairs to open the double helix
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none of the above
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catalyzes the joining of Okazaki fragments into a continuous strand, re-anneals semi-conservative strands
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removes the RNA primer and replaces it with DNA
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Detailed explanation-1: -DNA ligases are best known for their role in joining adjacent Okazaki fragments at the lagging strand of the replication fork; however, they are essentially involved in any process that requires sealing of phosphodiester bonds from the DNA backbone.
Detailed explanation-2: -The role of DNA ligase in DNA replication is to join the Okazaki fragments synthesized on the lagging strand into a continuous strand. In the case of leading strand, the nucleotides are added to the growing 3’ end continuously.
Detailed explanation-3: -These small pieces of newly synthesized DNA (called Okazaki fragments after their discoverer) are joined by the action of DNA ligase, forming an intact new DNA strand.
Detailed explanation-4: -On the lagging strand, DNA synthesis restarts many times as the helix unwinds, resulting in many short fragments called “Okazaki fragments.” DNA ligase joins the Okazaki fragments together into a single DNA molecule.