Transcription directionality — During RNA synthesis, what RNA sequence is produced from the DNA template strand 5′-T p A p G p C-3′ (written 5′→3′ on the template)?

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Solve this multiple-choice question and choose the correct option.

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Introduction:Transcription produces RNA complementary to the DNA template and antiparallel to it. Getting orientation correct is essential for predicting RNA sequences from DNA and vice versa. Given Data / Assumptions: Template strand is explicitly given 5′→3′ as T–A–G–C. RNA uses U instead of T. Polymerases synthesize RNA 5′→3′ while reading the template 3′→5′. Concept / Approach:Because the provided template is written 5′→3′, we must first reverse its orientation to align with the polymerase reading direction. Complement bases accordingly and then express the RNA in the standard 5′→3′ direction. Step-by-Step Solution: 1) Template (given) 5′→3′: T–A–G–C.2) Reverse to 3′→5′ for reading: C–G–A–T.3) Complement to RNA (5′→3′ product): G–C–U–A.4) Therefore, RNA sequence is 5′-G C U A-3′ (option b, noting U for uracil). Verification / Alternative check:Check against the non-template (coding) strand: it would be 5′-G C T A-3′ in DNA, so replacing T with U gives 5′-G C U A-3′ in RNA, matching the result. Why Other Options Are Wrong: a) Uses T instead of U and has wrong orientation.c) Contains T, not U, and mismatches base pairing.d) Incorrect base order; A U C G would pair with T A G C in the same orientation, which is not antiparallel.e) Not reported in the standard 5′→3′ product orientation requested. Common Pitfalls:Forgetting antiparallel orientation; writing T in RNA; failing to reverse the template before complementing. Final Answer:5′-G p C p U p A-3′.

Transcription directionality — During RNA synthesis, what RNA sequence is produced from the DNA template strand 5′-T p A p G p C-3′ (written 5′→3′ on the template)?

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