The group of three nitrogen bases that codes for one specific amino acid is called a codon. A codon is a sequence of three nucleotides found in mRNA (messenger RNA) molecules. The sequence of codons in the mRNA determines the sequence of amino acids in a protein during the process of protein synthesis. Each codon codes for a specific amino acid or a signaling function such as the start or stop of protein synthesis. The genetic code, which is the set of rules that defines how codons are translated into amino acids, is nearly universal across all organisms.
