Position-Specific Weight Matrix Tables Show Relatively Few Substitutions for Cysteine

Multiple Choice

Position-specific weight matrix tables show relatively few substitutions for cysteine and tryptophan compared with other proteins. Which of the following are possible explanations for this? Please select all that apply.

A) Cysteine and tryptophan are more likely to have essential roles in the mature protein than other amino acids
B) Cysteine and tryptophan are larger than other amino acids.
C) Cysteine and tryptophan have unusual structures
D) The codons for cysteine and tryptophan are similar to a stop codon