OBJECTIVE LIFE SCIENCE
MOLECULAR BIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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DNA polymerase
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Primase
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Ligase
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Topoisomerase
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Detailed explanation-1: -Primase enzyme binds itself at the end of the leading strand. This primer acts as the starting point of DNA synthesis. Hence, ligase is used on the lagging strand.
Detailed explanation-2: -What is the action of DNA ligase in DNA replication? DNA ligase fuses together Okazaki fragments on the lagging strand during replication. It does this by covalently linking the 3’ hydroxyl group on ribose sugars and the 5’ phosphate ends of nucleotides to form a phosphodiester (sugar-phosphate) bond.
Detailed explanation-3: -Okazaki fragments are short sequences of DNA nucleotides (approximately 150 to 200 base pairs long in eukaryotes) which are synthesized discontinuously and later linked together by the enzyme DNA ligase to create the lagging strand during DNA replication.