1) In tomatoes, stem color and fruit color are determined by two independently assorting genes. At one gene, purple stem (P) is dominant to green stem (p). At the other gene, yellow fruit (Y) is dominant to red fruit (y). Consider a cross between two tomato plants heterozygous for both these alleles:
a. Specify the genotypes of all gametes that can be made by one of these plants, and in what proportions they will occur. (Note: Give the genotypes of the gametes, not the offspring.)
b. What proportion of the offspring are expected to be heterozygous for both genes?
c. What proportion are expected to have genotype pp YY?
d. What proportion are expected to have green stems?
e. What proportion are expected to have yellow fruit?
f. What proportion are expected to have green stems and red fruit?
g. What proportion are expected to have purple stems and red fruit?
h. If a double heterozygous plant were crossed with a plant that has green stems and red fruit, what offspring phenotypes would be expected and in what proportions?