In a Plant Species, You Notice That Purple and Yellow

Essay

In a plant species, you notice that purple and yellow leaf colors, as well as hairy and smooth stems, segregate. In this species, yellow (P) is dominant to purple (p), and hairy (S) is dominant to smooth (s). You cross a plant with purple leaves and hairy stems to a plant with yellow leaves and hairy stems and generate the following progeny: $\begin{array}{|l|l|}\hline \begin{array}{l}\text { Progeny } \\\text { Class }\end{array} & \text { Phenotypes } \\\hline 1 & 68 \text { yellow leaves, hairy stems } \\2 & 66 \text { purple leaves, hairy stems } \\3 & 22 \text { purple leaves, smooth stems } \\4 & 25 \text { yellow leaves, smooth stems } \\\text { Total: } & 181\end{array}$ a. Indicate the most likely genotypes for each parent.
b. Propose a hypothesis to explain the progeny results. Based on this hypothesis, what ratios are expected for each of the four classes of progeny?
c. Using the chi-square method, test your hypothesis and indicate whether you accept or reject it.