The pea (Pisum sativum) has 7 distinct chromosomes. Mendel examined 7 genes, but not all were on different chromosomes, as shown in the table below. If he had done dihybrid crosses with certain pairs of traits, he might never have figured out the laws of inheritance…or maybe he would have discovered linkage too! Relationship between modern genetic terminology and character pairs used by Mendel Character pair used by Seed colour Seed coat and flowers, Mature pods, Inflorescences, Alleles in Located in modern terminology chromosome Mendel yellow green coloured-white smooth expanded-wrinkled i-i indented from leaf axils-umbellate in Plant height, Uaripe pods, Mature seeds, top of plant 1m-around 0.5 m green-yellow Fa-fa Le-le Gp-xp R-r c 1975 Nature Publishing Group. Why didn’t Gregor Mendel find linkage? By Blixt S., Nature, 256, 206. Draw the mating of a tall plant with yellow seeds and purple flowers with a short plant with green seeds and white flowers. Assume that the first plant is heterozygous at all 3 loci (Le, I and A) and the second plant is homozygous 3) Reproduce the previous mating, but with crossing over between two loci. a. Draw the steps of meiosis WITH CROSSING OVER between two loci. b. Use the gametes from cach parent in a Punnett square. c. List all possible offspring genotypes that result and their corresponding phenotypes. d. How does crossing over affect the types of offspring produced? What f actor is most important determining the proportions of each type?