Which molecule transfers amino acids during translation?

• A. Codon
• B. Amino acid
• C. tRNA
• D. Ribosome

Answer: (C)

tRNA is the molecule that transfers amino acids during translation. It acts as the adaptor between the mRNA codon and the amino acid: each tRNA carries a specific amino acid attached at its 3' end by an aminoacyl-tRNA synthetase, and its anticodon pairs with the corresponding codon on the mRNA inside the ribosome. This pairing ensures the correct amino acid is added to the growing polypeptide. When a charged tRNA enters the ribosome at the A site, its amino acid is transferred to the growing chain on the tRNA in the P site, forming a peptide bond, and the tRNA is released to pick up another amino acid. The other options don’t transfer amino acids: a codon is the mRNA triplet that specifies which amino acid to add; an amino acid is the cargo itself; the ribosome is the molecular machine that catalyzes peptide bond formation but does not carry amino acids between locations.