1) The E. coli gene lacYencodes a protein called lactose permease, needed for digestion of lactose. A mutation in this gene at codon 64 changed the normalglycine codon into a valine codon. The mutant protein isnon-functional. However, function is restored by a second mutationthat changes codon 50 from an alanine codon to a threonine codon.Are the following terms appropriate or inappropriate to describethis second mutation? Briefly explain each answer.
a. Reversion
b. Intragenic suppressor
c. Intergenic suppressor
d. Missense mutation