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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holds DNA polymerase in place during strand extension
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extends an Okazaki fragment
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catalyzes the joining of Okazaki fragments into a continuous strand
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Detailed explanation-1: -In prokaryotic cells, polymerase III is the major replicative polymerase, functioning in the synthesis both of the leading strand of DNA and of Okazaki fragments by the extension of RNA primers.
Detailed explanation-2: -The dimeric structure of the DNA polymerase III holoenzyme couples leading and lagging strand DNA syntheses during replication. Leading strand synthesis (bottom strand) is continuous and processive, but lagging strand synthesis must reinitiate many times during replication of the chromosome.
Detailed explanation-3: -The two main functions of DNA (Deoxyribonucleic acid) polymerase III are as follows: To add nucleotides to the RNA primer. To synthesize the leading and lagging strands of DNA.
Detailed explanation-4: -There are two molecules of DNA polymerase III at a replication fork, each of them hard at work on one of the two new DNA strands. DNA polymerases can only make DNA in the 5’ to 3’ direction, and this poses a problem during replication.