Question

A fly has two alleles for the color of its eyes. The green allele is recessive, and is represented by q. The blue allele is dominant, and is represented by p. If 44 of 100 organisms are green, what is p?

Answer 1

Answer:

p = 0.34

Explanation:

The green allele is recessive, meaning two copies of q (qq) are required to be green. Conversely, animals that are either pp or pq will be blue.

If 44 organisms are green, that means 44 are qq.

For genotype frequencies, the equation is:

homozygous dominant genotype + heterozygous + homozygous recessive = 100%

Which is denoted as

p² + 2pq + q² = 1

We know that q² = 44/100 = 0.44

To work out q, we can do $\sqrt{0.44}$ = 0.66

For allele frequencies, the total must add up to 100%, so

p + q =1

We know that q= 0.66

So p = 0.34, because 0.66 + 0.34 = 1