GENETICS AND EVOLUTION
MOLECULAR BASIS OF INHERITANCE
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
primase
|
|
|
topoisomerase
|
|
|
DNA polymerase
|
|
|
helicase
|
Detailed explanation-1: -The DNA polymerase enzyme reads the DNA sequence during proofreading. As a result, the right answer is (c) DNA Pol.
Detailed explanation-2: -In bacteria, all three DNA polymerases (I, II and III) have the ability to proofread, using 3’ → 5’ exonuclease activity. When an incorrect base pair is recognized, DNA polymerase reverses its direction by one base pair of DNA and excises the mismatched base.
Detailed explanation-3: -Replicative DNA polymerases possess 3′ → 5′ exonuclease activity to reduce misincorporation of incorrect nucleotides by proofreading during replication.
Detailed explanation-4: -A proofreading polymerase is an enzyme that replicates DNA with a higher degree of fidelity than standard Taq. No polymerase is infallible: at some point, the polymerase will add an incorrect nucleotide onto the growing DNA chain, resulting in a mismatch between the template and the newly synthesize strand.