Originally Posted by lemontea88
Wow this is a really good question! I know methionine is special, but didn't know Tryptophan is special too!
Thx lee, do come up with more questions please!
So you got the right answer
The genetic code is redundant and degenerate in that several codons code for the same amino acid so that a change in the third nucleotide may not matter and this is how silent mutations occur. The exceptions are methionine and tryptophan both of which have only one codon coding for them.
The AUG for methionine also serves as a start codon.