Which enzyme synthesizes RNA during transcription?

Which enzyme synthesizes RNA during transcription?

• A. DNA polymerase
• B. Ribosome
• C. Helicase
• D. RNA polymerase

Answer: (D)

Transcription is the process of making an RNA copy from a DNA template. The enzyme that carries out this synthesis is RNA polymerase. It binds to promoter regions, unwinds a small portion of DNA, and then adds ribonucleotides to the growing RNA strand in the 5' to 3' direction, using the DNA template to guide the sequence. RNA polymerase can start RNA synthesis de novo (without a primer), which is a key difference from DNA polymerase. The other options have different roles: the ribosome translates mRNA into protein, helicase unwinds DNA but does not synthesize RNA, and DNA polymerase builds DNA during replication. Thus, RNA polymerase is the enzyme that synthesizes RNA during transcription.

Transcription is the process of making an RNA copy from a DNA template. The enzyme that carries out this synthesis is RNA polymerase. It binds to promoter regions, unwinds a small portion of DNA, and then adds ribonucleotides to the growing RNA strand in the 5' to 3' direction, using the DNA template to guide the sequence. RNA polymerase can start RNA synthesis de novo (without a primer), which is a key difference from DNA polymerase. The other options have different roles: the ribosome translates mRNA into protein, helicase unwinds DNA but does not synthesize RNA, and DNA polymerase builds DNA during replication. Thus, RNA polymerase is the enzyme that synthesizes RNA during transcription.