Question

Under normal conditions, a population is in Hardy-Weinberg equilibrium at 'gene A' and the frequency of alleles A = 0.5. Under drought conditions, the aa genotype is lethal (waa = 0). What will be the frequency of the a allele if the population is exposed to drought conditions for 4 generations? Spell out your answer.

Answer 1

The frequency of the a allele will be 0.75 after 4 generations of drought conditions.

Step-by-step explanation:

The frequency of the a allele can be calculated using the Hardy-Weinberg equation: p² + 2pq + q² = 1

Given that the aa genotype is lethal under drought conditions (waa = 0), we can assume that the frequency of the aa genotype will be 0 in the population. This means that q² = 0.

If the population is in Hardy-Weinberg equilibrium at gene A and the frequency of alleles A = 0.5, then p = 0.5.

Using the equation, we can calculate the frequency of the a allele:

1 = p² + 2pq + q²

1 = (0.5)² + 2(0.5)(q) + 0

1 = 0.25 + q

q = 0.75

Therefore, the frequency of the a allele will be 0.75 after 4 generations of drought conditions.