Marlin Keim has red-green colour blindness. His wife Latrice has normal vision. There has never been an incidence of red-green colour blindness in Latrice’s family. They have identical twin girls one of which has normal vision (Joan) and one is colour-blind (Hannah). Joan married Tom and has a son, Craig, with normal vision. Hannah married Geoff and had 3 sons: Jack, Mark and Andrew in that order. Jack and Andrew have normal vision while Mark is colourblind. a. Draw the Keim family pedigree. b. Explain how Joan and Hannah can have different vision if they are identical twins. To study Mendel’s principles, a strain of light brown mice, were crossed with a strain of dark brown mice. All F_1 were dark brown. In the F_2, 42 were dark brown and 15 were light brown. Is this consistent with the principle of segregation? (Use a chi-square test to help you.) The 42 dark brown mice from question 1 were crossed to light brown mice. Thirty of these mice produced litters composed of both dark and light brown mice, while the other 12 only produced dark brown offspring. Is this result consistent with the principle of segregation?