You now know thatinheritance of eye color in fruit flies is sex-linked: The gene encoding eye color is located on the X chromosome, and there is no corresponding gene on the Ychromosome.How would the inheritance pattern differ if the gene for eye color were instead located on an autosome (a non-sex chromosome)? Recall that for autosomes, bothchromosomes of a homologous pair carry the same genes in the same locations.Suppose that a geneticist crossed a large number of white-eyed females with red-eyed males.Consider two separate cases:Case 1: Eye color exhibits sex-linked inheritance.Case 2: Eye color exhibits autosomal (non-sex-linked) inheritance. (Note: In this case, assume that the red-eyed males are homozygous.)For each case, predict how many of the male and female offspring would have red eyes and white eyes.Drag the correct numbers on the left to complete the sentences on the right. Numbers can be used once, more than once, or not at all.1. If there were 100 female offspring, _______would have red eyes and ______ would have white eyes.2. If there were 100 male offspring, _______would have red eyes and ______would have white eyes.3. If there were100 female offspring, ______would have red eyes and _____ would have white eyes.4. If there were 100 male offspring, _____ would have red eyes and _____ would have white eyes. Label- 0, 25, 50, 75, 100
Case 1 1)100,0 2)0,100 Case 2 White is different from the other people. A is a letter. A AA Aa. It's a Aa. 3)0,100 (since female white eyed only recessive homozygous present) 4)75,25 (Normal case) This explanation is what my answers are based on. The reciprocalcross was performed by Morgan. A white-eyed female and a red-eyed male are having sex. He was able to find different results. Although, the F1 progeny were 50% female and 50% male as before but all the female flies were red-eyed and all the males werewhite-eyed. In F2 50% female and 50% male and 50% red eyed and 50% white eyed as well. The male received the X chromosome carrying the wild type allele from their mother.
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