What must the mismatch repair system be able to distinguish in order to tell which nucleotide of a mismatched pair to replace?
A)It must be able to distinguish the newly-made strand from the parental strand.
B)It must be able to distinguish which chain has more important genetic information.
C)It must be able to distinguish which chain contains the ribose sugars.
D)It must be able to distinguish which chain has a higher G-C content.

Question

Quizplus · Accepted Answer

The mismatch repair system must be able to distinguish between the newly-made strand and the parental strand in order to replace the correct nucleotide of the mismatched pair. This is because during DNA replication, the parental strand serves as a template for the newly-made strand, and any errors in base pairing will result in a mismatch between the two strands. Therefore, the mismatch repair system must be able to differentiate between the two strands to correctly identify which nucleotide needs to be replaced. The other answer choices are not relevant to the process of mismatch repair.

What Must the Mismatch Repair System Be Able to Distinguish