Answer: RNA polymerase II.
- A RNA polymerase I
- B RNA polymerase II
- C RNA polymerase III
- D RNA polymerase IV
Correct answer: B. RNA polymerase II
Explanation: RNA polymerase II transcribes the heterogeneous nuclear RNA (hnRNA), the precursor that is processed into mature mRNA.
Helicase unwinds the double helix at the replication fork; one new strand (leading) is synthesised continuously toward the fork, while the other (lagging) must be made in short, separate Okazaki fragments because DNA polymerase only adds nucleotides 5'→3'.
Concept context
DNA structure, replication, transcription, translation, the genetic code, and gene regulation (lac operon). The single most important chapter for NEET molecular biology.