OBJECTIVE LIFE SCIENCE
MOLECULAR BIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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DNA ligase
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nucleotides
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DNA polymerase III
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Okazaki fragments
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Detailed explanation-1: -When she adds some DNA to the mixture, replication occurs, but each DNA molecule consists of a normal strand paired with numerous segments of DNA a few hundred nucleotides long. What has she probably left out of the mixture? DNA polymerase.
Detailed explanation-2: -Justification of correct answer. Option (c) is a DNA polymerase. The reverse ( 3’ to 5’ ) exonuclease activity of the DNA polymerase enzyme regulates the proofreading process, allowing them to delete improperly inserted bases from newly produced DNA and replace them with correct bases.
Detailed explanation-3: -Correct answer: The only false statement is that DNA replication of the lagging strand is continuous. The leading strand features continuous replication while the lagging stand is initially made up of discontinuous Okazaki fragments, which are sealed later by ligase.
Detailed explanation-4: -Primer synthesis marks the beginning of the actual synthesis of the new DNA molecule. Primers are short stretches of nucleotides (about 10 to 12 bases in length) synthesized by an RNA polymerase enzyme called primase.