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Genetics!Practice!Problems:!!Pedigree!Tables!
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Remember%the%following%when%working%pedigree%tables:%
1)%Circles%are%females%and%squares%are%males.%
2)%A%shaded%circle%or%square%indicates%that%a%person%has%the%trait.%
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The%pedigree%seen%below%is%for%colorblindness.%%Shaded%individuals%are%colorblind.%%First,%determine%the%
probable%genotype%of%persons%1%–%15;%%then,%answer%the%questions%below%the%table.%%%%
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How%did%you%determine%the%genotype%of%the%mother%at%3?%
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Number%8%was%colorblind%just%like%his%father.%%Where%did%the%son%at%8%get%his%allele%for%colorblindness?%
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Neither%numbers%1%nor%2%were%colorblind.%%How%did%they%have%a%colorblind%son%(6)?%
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What%must%be%the%genotypes%of%the%parents%of%a%colorblind%daughter?%%Explain.%
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If%number%13%marries%a%normal%man,%what%is%the%probability%that%their%sons%will%be%colorblind?%
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