Question

Within a population of butterflies, the color brown (B) is dominant over the color white (b) and 32% of all butterflies are white. Given this simple information, which is something that is very likely to be on an exam (teehee), calculate the following:
1. The percentage of butterflies in the population that are homozygous dominant
2. The number of heterozygous butterflies if the population contained 4,216 individuals

Answer 1

Answer:

48% Heterozygous of the population, 12% Homozygous dominant size.

Explanation:  

Given the characteristics of its population,

Brown (B) predominates over white (b) color.

Recessive phenotype frequency (Q)= 40%= 0.4

According to the Hardy-Weinberg principle, the frequency is given by P and Q for a population with the dominant and recessive trait, where P+Q=1 preserves the equilibrium of the population allele.

So then, P = 1-Q

P=1-0.4=0.6

Heterozygotic butterflies = 2PQ

So, 2PQ= 2x0.6x0.4=0.48

That is, 48 percent of people are heterozygous

Homozygous dominant individual frequency = 1-(40 + 48) = 12 i.e. 12%