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

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

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

Answer: (A)

During protein synthesis, the adaptor that delivers amino acids to the ribosome is transfer RNA, or tRNA. Each tRNA carries a specific amino acid and has an anticodon that base-pairs with a complementary codon on the mRNA, ensuring the correct amino acid is added in the growing chain. Amino acids are first attached to their matching tRNAs by enzymes called aminoacyl-tRNA synthetases, charging the tRNA for delivery. When the ribosome encounters a charged tRNA at the A site, the amino acid it carries is transferred to the nascent polypeptide held on the tRNA in the P site, forming a peptide bond via the ribosome’s RNA-based catalytic center. The ribosome then translocates, moving the tRNAs and leaving the growing chain ready for the next codon. In short, tRNA acts as the bridge between the genetic code carried by mRNA and the amino acids that compose the protein. By contrast, mRNA provides the template, rRNA is part of the ribosome’s machinery, and DNA stores the genetic information.

During protein synthesis, the adaptor that delivers amino acids to the ribosome is transfer RNA, or tRNA. Each tRNA carries a specific amino acid and has an anticodon that base-pairs with a complementary codon on the mRNA, ensuring the correct amino acid is added in the growing chain. Amino acids are first attached to their matching tRNAs by enzymes called aminoacyl-tRNA synthetases, charging the tRNA for delivery. When the ribosome encounters a charged tRNA at the A site, the amino acid it carries is transferred to the nascent polypeptide held on the tRNA in the P site, forming a peptide bond via the ribosome’s RNA-based catalytic center. The ribosome then translocates, moving the tRNAs and leaving the growing chain ready for the next codon. In short, tRNA acts as the bridge between the genetic code carried by mRNA and the amino acids that compose the protein. By contrast, mRNA provides the template, rRNA is part of the ribosome’s machinery, and DNA stores the genetic information.