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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DNA Helicase unwinds original DNA strand
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RNA Primase lays down RNA primer for new nucleotide bases.
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DNA polymerase builds new strands by bring in new nucleotide bases.
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Ligase knits together fragments on lagging strand
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Detailed explanation-1: -Which is the second step? RNA Primase lays down RNA primer for new nucleotide bases. DNA polymerase builds new strands by bring in new nucleotide bases.
Detailed explanation-2: -Step 2: Primer Binding. The leading strand is the simplest to replicate. Once the DNA strands have been separated, a short piece of RNA called a primer binds to the 3’ end of the strand. The primer always binds as the starting point for replication.
Detailed explanation-3: -RNA primase attaches a short RNA molecule called a primer to the DNA sequence, which is removed upon the completion of DNA replication. Another enzyme involved in gene expression is called RNA polymerase, which uses template DNA strands to form RNA molecules.
Detailed explanation-4: -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.