Which RNA delivers amino acids to the ribosome during protein synthesis?

• A. Messenger RNA
• B. Ribosomal RNA
• C. Transfer RNA
• D. Small Nuclear RNA

Answer: (C)

Transfer RNA serves as the adaptor that delivers amino acids to the ribosome during translation. Each tRNA carries a specific amino acid and has an anticodon that pairs with the corresponding codon on the messenger RNA, ensuring the amino acid is added in the correct order to the growing polypeptide. The amino acid is attached to the tRNA by aminoacyl-tRNA synthetase, which charges each tRNA with its proper amino acid. At the ribosome, the charged tRNA enters the A site, the amino acid forms a peptide bond with the chain in the P site, and the tRNA then moves through the ribosome for the next cycle. In contrast, messenger RNA provides the genetic code, ribosomal RNA forms the ribosome’s catalytic and structural core, and small nuclear RNA is involved in RNA splicing. So the RNA that actually delivers amino acids to the ribosome is transfer RNA.