GENETICS AND EVOLUTION
MOLECULAR BASIS OF INHERITANCE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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to help DNA polymerase for initiation
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To help RNA polymerase for initiation
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To help DNA polymerase for termination
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To help RNA polymerase for termination
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Detailed explanation-1: -Primers are oligonucleotides that are complementarily bound to a DNA template and from which DNA polymerases elongate. Special proteins are responsible for loading primase at the origin of replication so that leading strand DNA synthesis can commence.
Detailed explanation-2: -The synthesis of a primer is necessary because the enzymes that synthesize DNA, which are called DNA polymerases, can only attach new DNA nucleotides to an existing strand of nucleotides. The primer therefore serves to prime and lay a foundation for DNA synthesis.
Detailed explanation-3: -Primers are short stretches of DNA that target unique sequences and help identify a unique part of genome-let’s say, a gene. Primers are usually 18 to 25 nucleotides long. They can be synthesized in a special lab, and are used in many different ways.
Detailed explanation-4: -DNA synthesis requires a primer usually made of RNA. A primase synthesizes the ribonucleotide primer ranging from 4 to 12 nucleotides in length. DNA polymerase then incorporates a dNMP onto the 3’ end of the primer initiating leading strand synthesis.
Detailed explanation-5: -Primers bind to the template via complementary base pairs. Like other DNA polymerases, Taq polymerase can only make DNA given a primer, which is a short nucleotide sequence that provides a starting point for DNA synthesis.