Question

Which enzyme is responsible for synthesis of RNA from a DNA template?

• A. DNA polymerase
• B. RNA polymerase
• C. Reverse transcriptase
• D. DNA ligase

Hint:

Transcription (DNA to RNA) = RNA Polymerase.
Replication (DNA to DNA) = DNA Polymerase.
Translation (RNA to Protein) = Ribosomes.

Answer 1

The Correct Option is B

The enzyme responsible for the synthesis of RNA from a DNA template is RNA polymerase. Let's understand the roles of each enzyme mentioned in the options to see why RNA polymerase is the correct choice:

1. DNA polymerase: This enzyme synthesizes DNA using a DNA template during DNA replication. It does not synthesize RNA.
2. RNA polymerase: This enzyme is responsible for transcribing RNA from a DNA template. It initiates the process of transcription, where a specific segment of DNA is used as a template to produce complementary RNA strands. This process is essential for gene expression.
3. Reverse transcriptase: This enzyme catalyzes the synthesis of DNA from an RNA template. It is primarily associated with retroviruses, where the viral RNA is reverse transcribed into DNA, which can then integrate into the host genome.
4. DNA ligase: This enzyme seals breaks in the DNA backbone by forming phosphodiester bonds. It is essential during DNA replication and repair but is not involved in synthesizing RNA.

From the above explanations, it is clear that RNA polymerase is the enzyme that synthesizes RNA from a DNA template. Therefore, the correct answer is RNA polymerase.

This fundamental process of transcription is the first step of gene expression, highlighting the importance of RNA polymerase in cellular biology.