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Transfer RNA, or tRNA, is a crucial molecule in protein synthesis. Its primary role is to act as an adapter, bridging the gap between the genetic code carried by messenger RNA (mRNA) and the amino acid sequence of a protein. Each tRNA molecule has a specific structure that allows it to bind to a particular amino acid and also to recognize a corresponding codon on the mRNA.

The structure of tRNA is often depicted as a cloverleaf in two dimensions, but in three dimensions it folds into an L-shape. This structure features two key sites: the amino acid attachment site, located at the 3' end, where a specific amino acid is covalently linked, and the anticodon loop, which contains a sequence of three nucleotides that is complementary to an mRNA codon.

During translation, ribosomes move along the mRNA molecule. As each codon is exposed, a tRNA molecule with the matching anticodon binds to it. The ribosome then catalyzes the formation of a peptide bond between the amino acid carried by the incoming tRNA and the growing polypeptide chain. This process continues until a stop codon is reached, signaling the end of protein synthesis. The specificity of tRNA in recognizing codons and carrying the correct amino acids is essential for the accurate production of proteins.