Question

A hypothetical population has two alleles for a gene: A and a. In a random sample of 100 individuals, 20 are homozygous for a, 20 are homozygous for A, and 60 are heterozygous. What is the frequency of A?

1) 20%

2) 25%

3) 50%

4) 60%

5) 80%

Answer 1

To find the frequency of allele A, you can consider each individual as having two alleles. Since 60 individuals are heterozygous (Aa), there are a total of 60 times 2 = 120 alleles from the heterozygous individuals. Additionally, there are 20 individuals with the homozygous genotype AA, contributing another 20 times 2 = 40 alleles. Therefore, the total number of A alleles is 120 (heterozygous) + 40 (homozygous AA) = 160. So 160 over 2 times 100 because A alleles by the total number of alleles in the population 2 alleles per individual * 100 individuals the answer will be 0.8 so 80%

Answer 2

To calculate the allele frequency of A in the hypothetical population, sums of A alleles from homozygous AA and heterozygous Aa individuals are counted and divided by the total number of alleles. The frequency of allele A is found to be 50% in this population.

Step-by-step explanation:

The question is regarding a hypothetical population with two alleles for a gene: A and a. To find the frequency of allele A, we need to count all the copies of allele A and divide by the total number of alleles present. Homozygous individuals for A (AA) contribute two A alleles each, and heterozygous individuals (Aa) contribute one A allele each. With 20 AA and 60 Aa individuals among 100 people total, we calculate the frequency as follows:

(2 alleles * 20 AA individuals) + (1 allele * 60 Aa individuals) = 40 + 60 = 100 alleles of A

Since each person has two alleles and there are 100 individuals, there are 200 alleles total:

Frequency of A = number of A alleles / total number of alleles = 100 / 200 = 0.5 or 50%

The frequency of allele A in the given population is 50%.