DNA Replication & Repair MCAT Practice Question
A molecular biologist studying DNA polymerase fidelity compares the error rates of replication in wild-type bacteria versus mutants lacking 3' to 5' exonuclease activity in DNA polymerase III. The mutant shows a 100-fold increase in error rate after replication. This demonstrates that the exonuclease activity functions primarily as which type of quality control mechanism?
Answer choices
- AProofreading during DNA synthesisCorrect answer
- BPost-replication mismatch detection
- CRemoval of RNA primers
- DResolution of replication forks
- EExcision of thymine dimers
- FF. Base excision repair of oxidative damage
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