Two true-breeding pea plants are crossed. One parent is round, terminal,
violet, constricted, while the other expresses the contrasting phenotypes of
wrinkled, axial, white, full. The four pairs of contrasting traits are
controlled by four genes, each located on a separate chromosome. In the
\(F_{1}\) generation, only round, axial, violet, and full are expressed. In the
\(\mathrm{F}_{2}\) generation, all possible combinations of these traits are
expressed in ratios consistent with Mendelian inheritance.
(a) What conclusion can you draw about the inheritance of these traits based
on the \(\mathrm{F}_{1}\) results?
(b) Which phenotype appears most frequently in the \(\mathrm{F}_{2}\) results?
Write a mathematical expression that predicts the frequency of occurrence of
this phenotype.
(c) Which \(\mathrm{F}_{2}\) phenotype is expected to occur least frequently?
Write a mathematical expression that predicts this frequency.
(d) How often is either \(P_{1}\) phenotype likely to occur in the \(F_{2}\)
generation?
(e) If the \(F_{1}\) plant is testcrossed, how many different phenotypes will be
produced?