Concept explainers
Form a small discussion group and decide on the most likely genetic explanation for each of the following situations;
a. A man who has red–green color blindness and a woman who has complete color vision have a son with red–green color blindness. What are the genotypes of these three people, and how do you explain the color blindness of the son?
b. Cross A performed by Morgan and shown in Figure 3.18 is between a mutant male fruit fly with white eyes and a female fruit fly from a pure-breeding, red-eye stock. The figure shows that 1237 F1 progeny were produced, all of them with red eyes. In reality, this isn’t entirely true. Among the 1237 F1 progeny were 3 male flies with white eyes. Give two possible explanations for the appearance of these white-eyed males.
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