This tutorial will take you step by step through the question. In cucumbers, dull fruit (D) is dominant to glossy fruit (d), and orange fruit (R) is dominant to cream-colored fruit (r). The gene that codes for dull versus glossy assorts independently from the gene that codes for orange versus cream-colored. A plant that has dull and orange fruits is crossed to a plant that has dull and cream-colored fruits. The cross produces eight total progeny, with three plants that have dull and orange fruits, three plants with dull and cream-colored fruits, one plant with glossy and orange fruits, and one plant with glossy and cream-colored fruits.
Determine progeny phenotypic ratios - texture. To determine the actual genotype of the parents from among the possible genotypes identified in the previous step, separate the cross into two single-locus crosses, looking at the inheritance of each trait by itself. Start with the texture characteristic.
What is the fraction that represents the number of dull progeny?
What is the fraction that represents the number of glossy progeny?
What is the ratio of dull progeny to glossy progeny?