MORE MONOHYBRID CROSS PROBLEMS
1. In summer squash, white fruit color is dominant. Yellow is recessive. A squash plant that is homozygous for
white is crossed with a homozygous yellow one. Predict the appearance of
a. the F1 generation
b. the F2 generation
c. the offspring of a cross between an F1 individual and a homozygous white individual
2.
In garden peas, inflated pod is dominant and constricted pod is recessive. If a plant homozygous for inflated
pods is crossed with a plant homozygous for constricted pod, what ratio of phenotypes & genotypes would you
expect to find in the F2?
3.
In guinea pigs, short hair is dominant and long hair is recessive. A shorthaired male and a shorthaired female
produced mostly shorthaired offspring, but a few were long haired. Show how you can determine the
genotypes of the parents.
4.
In laboratory mice, the normal gray color is dominant over albino color. Starting with purebred albino and
purebred gray as parents, what is the ratio of phenotypes in the F2 generation?
5.
A purple-flowered pea plant is crossed with a white-flowered pea plant. All the F1 plants produced had purple
flowers. When the F1 plants were allowed to self-pollinate, 401 of the F2s had purple flowers and 131 had white
flowers.
a. What color is dominant? Recessive? How do you know?
b.
What are the genotypes of the parental and F1 generation plants?