<prompt> All of the following are synonymous codon pair EXCEPTCAU CACAUU AUCAUG AUAAAU AAC  <response>: Synonymous codons Codons that specify the same amino acids. E.g- GGA, GGG, GGU, and GGC codes for glycine Methionine is coded by AUG only. So, there is no synonymous codon for methionine. 