In the overview of transcription, what is the primary role of RNA polymerase?

• A. It unwinds DNA ahead of the replication fork and synthesizes new DNA strands.
• B. It transports amino acids to the ribosome by matching anticodons to codons.
• C. It joins exons together and removes introns from the primary RNA transcript.
• D. It binds the DNA template and catalyzes synthesis of an RNA strand by adding ribonucleotides in the $5\prime \to 3\prime$ direction.

Answer: (D)

Verified step by step guidance

1. Understand that RNA polymerase is an enzyme involved in the process of transcription, where RNA is synthesized from a DNA template.
2. Recall that transcription involves reading the DNA template strand to create a complementary RNA strand.
3. Recognize that RNA polymerase binds to the DNA at a specific region called the promoter to initiate transcription.
4. Know that RNA polymerase catalyzes the formation of phosphodiester bonds between ribonucleotides, extending the RNA strand.
5. Remember that RNA synthesis occurs in the 5\' to 3\' direction, meaning nucleotides are added to the 3\' end of the growing RNA molecule.