GENETICS AND EVOLUTION
EVOLUTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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1:2:1
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3:1
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1:1
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1:0
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Detailed explanation-1: -Widow’s peak is a dominant trait, which shows even if there is only one allele. Here, in this case, the mother is heterozygous for the widow’s peak. So it can be denoted as Ww. The father has a straight hairline, which is a recessive trait compared to widow’s peak.
Detailed explanation-2: -The genotypes WW and Ww will produce a widow’s peak (the dominant phenotype) and the ww genotype will produce no widow’s peak (the recessive phenotype).
Detailed explanation-3: -As we can see, there is a 3/4 chance that the offspring will have a widow’s peak. Both the Ww and WW genotypes will give the offspring a widow’s peak since the widow’s peak allele, W, has complete dominance over the straight hair allele.
Detailed explanation-4: -The widow’s peak gene is dominant over the straight hairline gene; when they occur together a person will have a hairline with a widow’s peak.
Detailed explanation-5: -Answer and Explanation: The correct answer: Among the following genotypes the heterozygous genotypes are: 3. Aa and 4.