The correct answer is (A) 3ʹ TAC 5ʹ.​

Anticodons on tRNA pair antiparallel with mRNA codons during translation, and the question asks for the corresponding DNA code, which refers to the template strand sequence.​

Step-by-Step Reasoning

The anticodon is given as 3ʹ-AUG-5ʹ, so it pairs with the mRNA codon 5ʹ-UAC-3ʹ via complementary base pairing (A-U, U-A, G-C).​

mRNA is transcribed from the DNA template strand, which must be complementary and antiparallel: for 5ʹ-UAC-3ʹ mRNA, the template DNA is 3ʹ-ATG-5ʹ? No—for mRNA 5ʹ-U A C-3ʹ, template DNA reads 3ʹ-A T G-5ʹ (T pairs with A/U, A with T, G with C). Wait, correction: RNA U from DNA A (template), so template base opposite mRNA U is A; opposite A is T; opposite C is G. Thus, template DNA is 3ʹ-ATG-5ʹ. But options lack this exactly? Standard: template DNA 3ʹ-ATG-5ʹ transcribes to mRNA 5ʹ-UAC-3ʹ.​

In DNA notation, strands are often written 5ʹ→3ʹ, but here options match directions given. The “corresponding code” means the template strand triplet that dictates this codon.​

Option Analysis

• (A) 3ʹ TAC 5ʹ: Incorrect for template; this is coding/sense strand 3ʹ→5ʹ (or reverse of usual 5ʹ-ATG-3ʹ coding). But wait, for codon UAC, coding DNA is 5ʹ-TAC-3ʹ (same as mRNA with T/U), template 3ʹ-ATG-5ʹ. Not matching A directly? Re-eval: actually, mistake—mRNA 5ʹ-UAC-3ʹ means template DNA base-by-base: position1 (5ʹU): template 3ʹA; pos2 A: template T; pos3 C: template G—so 3ʹ-ATG-5ʹ template. None match ATG 3ʹ-5ʹ exactly? Option C is 3ʹ ATG 5ʹ—yes!​

Correction from logic and sources: anticodon 3ʹAUG5ʹ pairs mRNA codon 5ʹUAC3ʹ. DNA template that produces mRNA 5ʹUAC3ʹ is 3ʹATG5ʹ (A→U, T→A, G→C). So (C) 3ʹ ATG 5ʹ.​

But PYQ lists options, and standard biology confirms template is 3ʹ-ATG-5ʹ for Met codon AUG, but here for UAC it’s ATG template? No—for AUG mRNA (Met), template 3ʹTAC5ʹ! Let’s fix:

Standard start codon mRNA 5ʹAUG3ʹ, template DNA 3ʹTAC5ʹ, coding 5ʹATG3ʹ.

For anticodon 3ʹAUG5ʹ, pairs mRNA 5ʹUAC3ʹ (Tyr codon).​

Template DNA for mRNA 5ʹUAC3ʹ: template 3ʹATG5ʹ (3ʹA (for U), T (for A), G (for C)5ʹ). Yes, so (C) 3ʹ ATG 5ʹ.​

Why some sources? PYQ from GATE/CSIR shows options, and logic points C. But earlier thought A for Met, but no—this is unknown aa, for UAC it’s ATG template.​

• (A) 3ʹ TAC 5ʹ: Template for mRNA AUG (Met); wrong codon.​

• (B) 5ʹ TAG 3ʹ: Coding-like for stop, not matching.​

• (C) 3ʹ ATG 5ʹ: Correct template for mRNA 5ʹUAC3ʹ.​

• (D) 5ʹ ATG 3ʹ: Coding strand for Met (AUG mRNA), not template.​

The anticodon 3ʹ AUG 5ʹ DNA sequence question tests central dogma understanding in molecular biology, vital for CSIR NET Life Sciences.​

This MCQ from past papers like GATE Life Sciences emphasizes template strand identification.​

Why Anticodon Pairs with Codon

tRNA anticodon 3ʹ-AUG-5ʹ base-pairs antiparallel to mRNA codon 5ʹ-UAC-3ʹ (A-U, U-A, G-C).​

DNA Template Strand Derivation

DNA template strand transcribes mRNA: template 3ʹ-ATG-5ʹ → mRNA 5ʹ-UAC-3ʹ (no T in RNA). This matches option (C).​

Common Exam Pitfalls

• Confusing template vs. coding strand: Coding is 5ʹ-TAC-3ʹ here.

• Directionality: Options specify 3ʹ-5ʹ or 5ʹ-3ʹ.

• Forgetting RNA uses U, DNA T.​

Master anticodon 3ʹ AUG 5ʹ DNA sequence for competitive exams like CSIR NET.​