A plant that lacks the function of gene A (genotype aa) would produce mutant, white flowers that looked just like the flowers of a plant that lacked the function of gene B (genotype bb). (The genetics...A plant that lacks the function of gene A (genotype aa) would produce mutant, white flowers that looked just like the flowers of a plant that lacked the function of gene B (genotype bb). (The genetics of two loci are discussed more in the following chapters.) Both A and B are enzymes in the same pathway that leads from a colorless compound#1, thorough colorless compound#2, to the purple pigment.
