Which RNA molecule acts as adaptor between amino acids and mRNA during translation?

• A. mRNA
• B. tRNA
• C. rRNA
• D. DNA

Answer: (B)

In translation, the adaptor between amino acids and the mRNA template is transfer RNA. Each tRNA carries a specific amino acid and has an anticodon that base-pairs with the corresponding codon on the mRNA, so the correct amino acid is incorporated into the growing polypeptide chain. This two-part role—holding the amino acid on one end and recognizing the mRNA codon on the other—lets tRNA bridge the genetic code in the mRNA to the actual amino acid sequence. Enzymes called aminoacyl-tRNA synthetases charge the tRNAs with their correct amino acids, ensuring accuracy. The mRNA provides the sequence information to be read, but it does not deliver amino acids itself. The rRNA is part of the ribosome, helping catalyze peptide bond formation, and DNA stores genetic information.