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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the correct nucleotide.
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the sugar-phosphate backbone.
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DNA polymerase.
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one DNA strand.
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Detailed explanation-1: -When new DNA molecules are formed, almost all errors are detected and fixed by. the correct nucleotide.
Detailed explanation-2: -A DNA polymerase then replaces the missing section with correct nucleotides, and an enzyme called a DNA ligase seals the gap 2. Mismatch repair. A mismatch is detected in newly synthesized DNA.
Detailed explanation-3: -During proofreading, DNA polymerase enzymes recognize this and replace the incorrectly inserted nucleotide so that replication can continue. Proofreading fixes about 99% of these types of errors, but that’s still not good enough for normal cell functioning.
Detailed explanation-4: -DNA replication is a highly accurate process, but mistakes can occasionally occur, such as a DNA polymerase inserting a wrong base. Uncorrected mistakes may sometimes lead to serious consequences, such as cancer. Repair mechanisms correct the mistakes.
Detailed explanation-5: -Most of these errors are corrected by DNA polymerase during replication with its inherent proofreading mechanism via its 3’-exonuclease activity. This mechanism allows for the polymerase to read the most recently placed base before adding the next one.