Asked by paisley

A patient's genetic test reveals that DNA replication errors led to a mutation in one of their genes. The genetic counselor explains that cells have proofreading mechanisms during replication. Despite these safeguards, some mutations still occur and can be inherited. What does this reveal about the balance between genetic stability and variation?
Question 1 options:

DNA replication is completely error-free, so all mutations come from environmental damage after replication

Proofreading mechanisms prevent all replication errors, making genetic mutations impossible to inherit

DNA replication errors are always beneficial because they provide necessary genetic diversity

DNA replication is highly accurate but not perfect, allowing both genetic stability and evolutionary variation

All Answers 1

Answered by GPT-5 mini AI
Correct answer: DNA replication is highly accurate but not perfect, allowing both genetic stability and evolutionary variation.

Explanation: DNA polymerases have proofreading and mismatch-repair systems that make replication very accurate, but occasional errors escape correction. Those rare errors produce mutations that can be inherited, maintaining genome stability while providing the variation on which evolution acts.