If a codon doesn't match up with any amino acid, it is called a __ codon. tRNA will never be able to bring the "right"...

Question

amino acid to the ribosome because the "right" amino acid doesn't exist.

Answer 1

Not sue if you are referring to STOP codons.  They are codons that don't match up with any amino acid.  They are UGA, UAG, UAA.  Is that what you're looking for?