In summer squash, white fruit color (W) is completely dominant over yellow fruit color (w). Show your
work in a punnett square for the following questions.
a. If you cross a yellow summer squash with a homozygous dominant white squash.
i. What is the phenotypic ratio? _________________________ ii. What is the genotypic ratio? _________________________
b. If you cross a yellow summer squash with a heterozygous white squash.
i. What percentage of offspring will be white? _________________________ ii. What percentage of offspring will be yellow? _________________________
a.
i. The phenotypic ratio will be all white summer squash (100% white).
ii. The genotypic ratio will be all heterozygous white summer squash (100% Ww).
b.
i. 50% of the offspring will be white.
ii. 50% of the offspring will be yellow.
Punnett square for b
To create a Punnett square for the cross between a yellow summer squash (ww) and a heterozygous white squash (Ww), we will represent the alleles for the white color as W and w.
| | W | w |
|------|-------|-------|
| w | Ww | ww |
| w | Ww | ww |
In this Punnett square, we can see that 50% of the offspring will have the genotype Ww, which corresponds to the white phenotype, and 50% will have the genotype ww, corresponding to the yellow phenotype.