In roses assume that red or yellow flower color is controlled by a single gene with two alleles. Crossing roses with yellow flowers with each other yields only offspring that produce yellow flowers, but when you cross roses with red flowers with each other you sometimes get offspring that produce yellow flowers. If you take a rose plant that is heterozygous for the flower color gene and cross it with another rose plant with red flowers that has had yellow-flowered offspring in the past, what are the predicted fractions for the possible phenotypes of the offspring?.