Question

Punnett squares are used to show possible combinations of alleles or to predict the probability of a trait occurring in offspring. A pansy that is homozygous for purple flowers (PP) is crossed with a pansy that is homozygous for pink flowers (pp).

A pansy with purple flowers. A pansy with pink flowers.

Which genotypes will be included for the offspring in the Punnett square for this cross?
PP, Pp, and pp
PP and pp
PP and Pp
Pp only
Mark this and return

Answer 1

The genotypes included for the offspring in the Punnett square for this cross are PP and Pp.

Since the parent plants are homozygous for purple and pink flowers, they can only produce gametes with the P and p alleles, respectively. When these gametes are combined, the only possible genotypes for the offspring are PP and Pp. The Punnett square for this cross is as follows:

P p

P PP Pp

p Pp pp

As you can see, the Punnett square shows that all of the offspring will have either the PP genotype (homozygous for purple) or the Pp genotype (heterozygous for purple). There will be no pp genotype (homozygous for pink) offspring.

Therefore, the genotypes included for the offspring in the Punnett square for this cross are PP and Pp.