PATHOLOGY MCQ
GENETICS AND DISEASE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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The genes for white eyes and small wings are recessive
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The genes for eye color and wing size show incomplete dominance
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The genes for eye color and wing size are close together on the same chromosome
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The genes for white eyes and small wings are codominant
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Detailed explanation-1: -The eye color gene is located on the X chromosome (one of the sex determining chromosomes of Drosophila). White eye color is recessive. When a red eyed male mates with white eyed females, their daughters will have red eyes, but their sons will have white eyes.
Detailed explanation-2: -In Drosophila, white eye colour is recessive X-linked trait while red eye colour is dominant. A white eyed female is crossed with red eyed male.
Detailed explanation-3: -Morgan’s Test Crosses In his initial test cross aimed at exploring the precise relationship between eye color and sex, Morgan bred white-eyed males (X wY) with wild-type red-eyed females (X +X +). This cross yielded only red-eyed offspring, as summarized in Table 3.
Detailed explanation-4: -A cross between white eyed female and red eyed male Drosophila gives rise red eyed females and white eyed male. Rarely this cross gives rise to white eyed females and red eyed males.