🏥 USMLE Exam Prep

During prokaryotic DNA replication, which enzyme is primarily responsible for removing RNA primers and replacing them with DNA nucleotides?

A DNA ligase
B DNA polymerase III
C DNA gyrase
D DNA polymerase I

✓ Correct Answer: Option D

DNA polymerase I has 5'→3' exonuclease activity to remove RNA primers and 5'→3' polymerase activity to fill in the gaps with DNA, a unique function in prokaryotic DNA replication.

💡 Why is D) the correct answer?

The correct answer to the question "During prokaryotic DNA replication, which enzyme is primarily responsible for removing RNA primers and replacing them with DNA nucleotides?" is Option D: DNA polymerase I.

The other options — A) DNA ligase, B) DNA polymerase III, C) DNA gyrase — are incorrect for this USMLE Exam Prep question. As explained above: DNA polymerase I has 5'→3' exonuclease activity to remove RNA primers and 5'→3' polymerase activity to fill in the gaps with DNA, a unique function in prokaryotic DNA replication.

📚 About This USMLE Exam Prep Practice Question

This 2-level USMLE Exam Prep question from the Step 1 – Basic Sciences topic is part of BrainForge Quiz's free exam preparation library. Each question includes the correct answer and a detailed explanation to help you understand the underlying concept, not just memorize the answer.

How to use this page: Read the question above, consider all four options (A through D), then check the highlighted correct answer and explanation. For active timed practice, start a free USMLE Exam Prep practice test or use flashcards for spaced repetition review.

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