Question

the genotype frequency of a population is the proportion of each genotype at a particular gene or set of genes. consider another population of 100 pea plants with genotype frequencies of 50% aa, 25% aa, and 25% aa. the genotype numbers of this population are 50 green pea homozygotes (aa), 25 yellow pea heterozygotes (aa), and 25 yellow pea homozygotes (aa). we can calculate the allele frequency of a by dividing the number of a alleles in the population (125) by the total number of alleles (200).

\\(\frac{125}{200}=0.625 = 62.5\\%\\)

because we are dealing with only two alleles in this example, we can calculate the allele frequency of a by subtracting the allele frequency of a from 100%.

100% - 62.5% = 37.5%

in a population that is experiencing natural selection, we will see a change in the frequency of phenotypes and the alleles that determine them. by understanding how to determine allele frequencies in a population, we can determine if a population has experienced evolution.

Explanation:

Step1: Calculate a allele frequency

The number of a alleles is calculated considering the contribution from each genotype. There are 50 aa individuals (each contributing 2 a alleles) and 25 Aa individuals (each contributing 1 a allele), so the number of a alleles is \(50\times2 + 25\times1=125\). The total number of alleles in a population of 100 diploid individuals is \(100\times2 = 200\). The frequency of a allele \(p=\frac{125}{200}=0.625 = 62.5\%\)

Step2: Calculate A allele frequency

Since there are only two alleles (A and a) in the population, the sum of their frequencies is 100%. So the frequency of A allele \(q = 100\% - 62.5\%=37.5\%\)

Answer:

The frequency of a allele is 62.5% and the frequency of A allele is 37.5%