Base-substitution mutations often change the amino acid specified by a codon. For each of the amino acid changes listed, determine which ones can result from a one–base-pair substitution. For those that can result from a one–base-pair substitution, give the possible wild-type and mutant codons, listing multiple possibilities if there is more than one option. (Use either Figure 9.13 or the genetic code in Table A to help solve this problem).

Wild-type       Mutant
a. Ser               Ala
b. Cys              Ser
c. Pro               Glu
d. Lys               Stop
e. Met               His
f. Met                Ile