In primrose flowers, the dominant allele of gene K is necessary to synthesize blue flower pigment. Otherwise the flowers are white. Blue pigment synthesis is inhibited by a dominant allele of gene D. In other words, plants with the genotype K-D- will not produce pigment (and their flowers will be white) because of the presence of the D allele. If two dihybrid plants (Kk Dd) are crossed what is the ratio of blue to white offspring in the progeny?

3/13

Explanation:

K_  gives blue flower pigment

kk gives white flower

The presence of D, either as K_DD or K_Dd results in white flower

Crossing 2 plants with KkDd genotype:

        KkDd   x   KkDd

Offspring:

KKD_ = 9/16 white flower

KKdd = 3/16 blue flower

kkDD = 3/16 white flower

kkdd = 1/16 white flower

Hence, the ratio of blue to white flower would be 3:13

See the attached image for the Punnet's square

format change of dna.  

cuz he is really really short, assuming an unorthodox and inherently unlucky configuration of elevator buttons…

explanation: