In his original studies of Figure 3.18, Morgan first suggested that the original white-eyed male had two copies of the white-eye allele. In this problem, let's assume that he meant the fly was XWYW instead of XWY. Are his data in Figure 3.18 consistent with this hypothesis? What crosses would need to be made to rule out the possibility that the Y chromosome carries a copy of the eye color gene?

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Experimental level 1.Cross the white-eyed male to a true-breeding red-eyed female. P generation Conceptual level XWY X X X 2. Record the results of the F1 generation. F1 generation This involves noting the eye color and sex of many offspring. XY male offspring and XX female offspring, both with red eyes 3. Cross F1 offspring with each other to obtain F2 offspring. Also record the eye color and sex of the F2 offspring. 4. In a separate experiment, perform a testcross between a white-eyed male from the F2 generation and a red-eyed female from the Fi generation. Record the results. F2 generation O+ IXWY:IXWY:IXXXX I red-eyed male: 1 white-eyed male: 2 red-eyed females XY XY:IX"X":1 X"X" I red-eyed male: I white-eyed male: I red-eyed female: I white-eyed female