Can someone explain in detail how to do this problem? You cross true-breeding re
ID: 1781 • Letter: C
Question
Can someone explain in detail how to do this problem? You cross true-breeding red-flowered plants withtrue-breeding, white-flowered plants, and the F1 are allred-flowered plants. The F2, however, occur in a ratio of 9 red : 6pale purple : 1 white. How many genes are involved in theinheritance of this color character? Explain why the F1 are all redand how the 9:6:1 ratio of phenotypes in the F2 occurred. Can someone explain in detail how to do this problem? You cross true-breeding red-flowered plants withtrue-breeding, white-flowered plants, and the F1 are allred-flowered plants. The F2, however, occur in a ratio of 9 red : 6pale purple : 1 white. How many genes are involved in theinheritance of this color character? Explain why the F1 are all redand how the 9:6:1 ratio of phenotypes in the F2 occurred.Explanation / Answer
There are two genes involved in this breeding. The parental flowers are AABB (red) and aabb (white). The F1 generation flowers are all therefore AaBb, and with the assumption that red is dominant, the F1 will all be red. Then when you combine the F2 generation flowers, 9 will be dominant, having A- and B- (it doesn't matter what the other allele is if one is dominant) and so 9 will be red. 6 will be dominant in either A or B, so there will be an intermediate phenotype, here pale purple. One will be completely recessive (aabb) and will be white.