Question

During DNA replication in eukaryotic cells, which of the following enzymes is responsible for removing RNA primers and filling the gaps with DNA nucleotides?

• A. DNA Polymerase III
• B. DNA Ligase
• C. DNA Polymerase I
• D. Helicase

Hint:

DNA Polymerase I removes RNA primers and replaces them with DNA; DNA Ligase seals the fragments afterward.

Answer 1

The Correct Option is C

- During DNA replication, the RNA primers laid down by primase need to be removed to allow DNA synthesis in those regions. 
- DNA Polymerase I has the unique ability to remove RNA primers using its 5 --- 3' exonuclease activity and simultaneously fill the gaps with DNA nucleotides, making (C) correct. 
- DNA Polymerase III is mainly responsible for synthesizing the new DNA strand but does not remove RNA primers, so (A) is incorrect. 
- DNA Ligase seals the nicks between Okazaki fragments but does not remove primers, so (B) is incorrect. 
- Helicase unwinds the DNA double helix but does not deal with primers, so (D) is incorrect. 
Answer: \(\boxed{\text{C}}\)