DNA-dependent RNA polymerase catalyses the polymerization in the direction:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 5′ → 3′
The two strands of DNA run in opposite directions, and DNA-dependent RNA polymerase can add nucleotides in one direction only. It reads the template strand, which has the polarity 3′ → 5′, and makes the new RNA chain in the 5′ → 3′ direction.
(1) 5′ → 3′ — Correct. New nucleotides are always added at the 3′ end of the growing RNA.
(2) 3′ → 5′ — Incorrect. This is the polarity of the template strand that the enzyme reads, not the direction in which the RNA is made.
(3) 5′ → 5′ — Incorrect. There is no such direction. A chain has a 5′ end and a 3′ end.
(4) 3′ → 3′ — Incorrect. For the same reason, there is no such direction.
Note: A similar question was also asked in CUET (UG) 2026 on 21-05-2026 (Slot 1).
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