In a population of 1000 plants, the frequency of the a allele is 5 percent. Suppose a fire causes the loss of 500 individuals who are homozygous for the A allele. In this case the fire caused the
frequency of a to change from ______ to ______.
so, the first one should be 0.05 (5%)
I am not sure how to calculate the second one.
a = 0.05
p + q = 1
p+ 0.05 = 1
p = 0.95
(0.95)^2= AA?
any hint ? thx
To calculate the frequency of the a allele after the fire, you need to consider the initial frequency of the a allele and the number of individuals who are homozygous for the A allele (AA genotype) lost in the fire.
Let's break it down step by step:
1. Calculate the initial frequency of the A allele (p):
Given that the frequency of the a allele is 5%, the frequency of the A allele can be calculated using the equation p + q = 1, where p represents the frequency of the A allele and q represents the frequency of the a allele. Rearranging the equation, p = 1 - q.
Since the frequency of the a allele is 5% (0.05), substitute it into the equation: p = 1 - 0.05 = 0.95.
2. Calculate the number of individuals with the AA genotype lost in the fire:
The total population size is 1000, and since the frequency of the a allele is given, we know that 5% of the population is aa genotype individuals.
Therefore, the number of individuals with the aa genotype is 0.05 * 1000 = 50.
Since the remaining individuals are homozygous for the A allele (AA genotype), we can determine the number lost by subtracting the number of aa genotype individuals from the total population size: 1000 - 50 = 950.
3. Calculate the new frequency of the a allele after the fire:
To calculate the new frequency of the a allele (q) after the fire, divide the number of individuals with the aa genotype lost in the fire (500) by the new total population size (500), because 500 plants were lost due to the fire.
q = 500 / 500 = 1.
4. Calculate the new frequency of the A allele after the fire:
Since p + q = 1, the new frequency of the A allele can be calculated by subtracting the frequency of the a allele (q) from 1:
p = 1 - q = 1 - 1 = 0.
Therefore, after the fire, the frequency of the a allele changed from 0.05 to 1, and the frequency of the A allele changed from 0.95 to 0.