Question
Question: In a population that is in Hardy Weinberg equilibrium, the frequency of a recessive allele for a cer...
In a population that is in Hardy Weinberg equilibrium, the frequency of a recessive allele for a certain hereditary trait is 0.20. What percentage of the individual in the next generation would be expected to show the dominant trait?
A. 16%
B. 32%
C. 64%
D. 96%
Solution
Hardy- Weinberg principle states that allele frequency in a population remains the same generation after generation if the population is not subjected to genetic drift, gene migration, mutation, genetic recombination, and natural selection.
Complete answer: In a given population the frequency of occurrence of alleles of a gene or a locus can be found out. This frequency is supposed to remain constant and even remain the same through the generations. Hardy- Weinberg principle stated it using an equation.
This principle says, the allele frequencies in a population remain stable from one generation to another, which is a state of genetic equilibrium, and a total of all allelic frequencies is equaled to one.
p2+2pq+q2=1
The frequency of recessive allele(q)= 0.2
Frequency of dominant allele will be= 1-0.2= 0.8
The frequency of homozygous dominant allele will be 0.64, and the frequency of a heterozygous dominant allele(2pq) will be = 0.32
The frequency of dominant individuals in the next generation will be 0.64+0.32=0.96
In percentage, it will be 96% .
So, the correct option is D. 96%.
Note: When frequency measured differs from expected values, difference indicates the extent of evolutionary change. Disturbance in genetic equilibrium or Hardy-Weinberg equilibrium. That is a change of frequency of alleles in a population is interpreted as resulting in evolution.
Five factors that usually affect Hardy-Weinberg equilibrium are gene migration, genetic drift, mutation, genetic recombination, and natural selection.