In a certain species of plant, flowers occur in three colors: blue, pink, and white. A pure-breeding pink plant is mated with a pure-breeding white plant. All of the F 1 are blue. When the blue F 1 plants are selfed, the F 2 plants occur in the ratio 9 blue : 3 pink : 4 white. The genotype that produces white is ww. The presence of one W allele allows pink or blue color to occur. The alleles at the hypostatic locus are B (blue) and b (pink).
-What is the genotype of the pink parent?
A) bb WW
B) bb Ww
C) Bb Ww
D) Bb ww
E) BB ww

Question

In a certain species of plant, flowers occur in three colors: blue, pink, and white. A pure-breeding pink plant is mated with a pure-breeding white plant. All of the F 1 are blue. When the blue F 1 plants are selfed, the F 2 plants occur in the ratio 9 blue : 3 pink : 4 white. The genotype that produces white is ww. The presence of one W allele allows pink or blue color to occur. The alleles at the hypostatic locus are B (blue) and b (pink). 
-What is the genotype of the pink parent?
A) bb WW
B) bb Ww
C) Bb Ww
D) Bb ww
E) BB ww

Quizplus · Accepted Answer

The pink parent must be homozygous for the pink allele (bb) and have at least one dominant W allele to allow pink color, so the genotype is bb WW.

In a Certain Species of Plant, Flowers Occur in Three