For the same plant population--where green seeds (G) are dominant to yellow seeds (g) and 25% of the population of 500 individuals show the recessive phenotype--how many individuals would you expect to be heterozygous for green seeds?

0.5 (500) = 250 individuals.

Explanation:

As given;

Green seeds (G) are dominant over yellow seeds (g);

25% show recessive phenotype, means 125 show recessive phenotype (yellow seed).

Let q² = recessive allele.

q² = 125/500

q² = 0.25

q = 0.5

p = 1-q = 0.5

p² = 0.25; so homozygous dominant for green seed=0.25 (500) = 125 individuals

Now, we can calculate the individuals which are heterozygous for green seeds are'

Heterozygous = 2pq

2pq = 2 (0.5) (0.5)

=0.5

so, 0.5 (500) = 250 indindidual are heterozygous for green seed.