If 500 males are AA and 500 females are Aa and they all mate

If 500 males are AA and 500 females are Aa and they all mate and produce one offspring after mating only once, then how many heterozygotes will there be in the next generation ?

Solution

The frequency of AA population is = 500/1000 = 0.5

The frequency of heterozygotes is = 500/1000 = 0.5

The frequency of allele A is = frequency of AA + ½ (frequency of Aa) = 0.5+1/2 (0.5) = 0.5+0.25 = 0.75

The frequency of allele a is = frequency of aa + ½ (frequency of Aa) = ½ (0.5) = 0.25

The number of AA progeny in the next generation is = 0.75*0.75 = 0.5625

The number of Aa individuals in the next generation is = 0.75*0.25 = 0.1875

No aa individuals will be there because males are homozygous dominant.