# If 90 out of 200 individuals in a population express the recessive phenotype, what is the frequency of the recessive allele?If 90 out of 200 individuals in a population express the recessive phenotype, what proportion of the population are expected to be heterozygotes?

Question
Asked Feb 18, 2019
37 views

If 90 out of 200 individuals in a population express the recessive phenotype, what is the frequency of the recessive allele?

If 90 out of 200 individuals in a population express the recessive phenotype, what proportion of the population are expected to be heterozygotes?

check_circle

Step 1

The above questions are based on the Hardy-Weinberg principle. According to this principle, the allele and genotype frequency of the population will remain constant from generation to generation. And this would only be possible if there are no evolutionary influences. There are five variables in the Hardy-Weinberg principle. These variables are as follows:-

p= frequency of the dominant allele

p2 = frequency of dominant homozygous allele

2pq = frequency of heterozygous allele

q = frequency of the recessive allele.

q2 = frequency of recessive homozygous allele

Step 2

According to the Hardy-Weinberg principle the equation for the expected allele frequency is

p + q = 1

The equation for the expected genotype is

p2 + 2pq + q2

Step 3

According to question there are 90 people with recessive phenotype out of the 200 people.  So,

Frequency of homozygous recessi...

### Want to see the full answer?

See Solution

#### Want to see this answer and more?

Solutions are written by subject experts who are available 24/7. Questions are typically answered within 1 hour.*

See Solution
*Response times may vary by subject and question.
Tagged in
ScienceBiology