In peas, a gene controls flower color such that R1 = purple and R2 = white. The purple allele is dominant to the white allele. In an isolated pea patch, there are 36 purple-flowering plants and 64 white-flowering plants. Assuming Hardy-Weinberg equilibrium, what is the value of q for this population?
A) 0.36
B) 0.64
C) 0.75
D) 0.80

Question

Quizplus · Accepted Answer

In Hardy-Weinberg equilibrium, the frequency of the two alleles in a population can be represented as p^2 + 2pq + q^2 = 1, where p is the frequency of the dominant allele, and q is the frequency of the recessive allele. Since white-flowering plants are recessive, the frequency of the white-flowering phenotype (q^2) can be calculated from the proportion of white-flowering plants in the population. With 64 white-flowering plants out of a total of 100 plants, q^2 = 64/100 = 0.64. Taking the square root of 0.64 gives q = 0.8.

In Peas, a Gene Controls Flower Color Such That R1