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updated: May 27, 2022


A codon is a DNA or RNA sequence of three nucleotides (a trinucleotide) that forms a unit of genomic information encoding a particular amino acid or signaling the termination of protein synthesis (stop signals). There are 64 different codons: 61 specify amino acids and 3 are used as stop signals.



Codon is the name we give a stretch of the three nucleotides, you know, one of A, C, G, or T, three of which in a row, that code for a specific amino acid, and so the genetic code is made up of units called codons where you have three nucleotides that code for a specific amino acid next to another three nucleotides, another three nucleotides, and another three nucleotides. And the cellular machinery, again the ribosome, that comes through and reads that genetic code, plugs in the correct amino acid that corresponds to each of the triplet code that's in the codon.