Transfer RNAs (tRNA) couple amino acids to their RNA codes. Each codon is supposed to be converted into either a specific amino acid in a protein or a specific instruction to the ribosome (e.g., start, stop, pause, etc). At one end, a transfer RNA presents a three-base codon. At the other, it grasps the corresponding amino acid. Transfer RNAs “read”, or “translate” , the messenger RNA through base pairing, the chemical attraction of A for T and C for G, just as the RNA sequence is “transcribed” from DNA by base pairing.