The mRNA codon is 5'-GAU-3'. Which anticodon on the tRNA pairs with it?
Answer and explanation
Correct answer: B. 3'-CUA-5'
- Step 1: Pairing is antiparallel and complementary (A-U, G-C). Step 2. G pairs with C, A with U, U with A: the anticodon is 3'-CUA-5'. Answer: 3'-CUA-5'. Why not the others: 3'-GAU-5' is identical to the codon; tRNA contains uracil, not thymine; 5'-CUA-3' is complementary but not antiparallel.
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