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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Replaces RNA primer at the lagging strand with DNA nucleotide
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Requires short primer before adding the new DNA nucleotide
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Adds DNA nucleotide at a free 3’ end of an existing chain
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Cannot initiate synthesis of a new DNA strand
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Detailed explanation-1: -Answer and Explanation: The answer to the question would be, option b. It can synthesize DNA in 5’ to 3’ direction.
Detailed explanation-2: -Primase synthesizes RNA primers complementary to the DNA strand. DNA polymerase III extends the primers, adding on to the 3’ end, to make the bulk of the new DNA. RNA primers are removed and replaced with DNA by DNA polymerase I. The gaps between DNA fragments are sealed by DNA ligase.
Detailed explanation-3: -The main function of the third polymerase, Pol III, is duplication of the chromosomal DNA, while other DNA polymerases are involved mostly in DNA repair and translesion DNA synthesis. Together with a DNA helicase and a primase, Pol III HE participates in the replicative apparatus that acts at the replication fork.
Detailed explanation-4: -So, the correct option is ‘RNA polymerase’