When pea plants from a pure-breeding strain with purple flowers are crossed with pea plants from a pure-breeding strain with white flowers, the F1 offspring all have purple flowers. However, the next generation (the F2 generation) contains plants with purple flowers and plants with white flowers.

Second generation offspring genotype

PP, Pp, Pp, pp

Phenotype of Second generation offspring

PP and Pp will be purple in color

and pp will be white in color

Explanation:

Let the allele for purple color of flowers be "P" and the allele for white color of flowers be "p"

Given in F1 generation pure-breeding strain with purple flowers are crossed with pea plants from a pure-breeding strain with white flowers

Genotype of pure-breeding purple flowers be "PP"

Genotype of pure-breeding white flowers be "pp"

Genotype of offspring after first generation cross will be "Pp"

Second generation cross

Pp * Pp

PP, Pp, Pp, pp

Thus,

PP and Pp will be purple in color

and pp will be white in color