Log onto: http://vcourseware3.calstatela.edu/VirtualFlyLab/IntroVflyLab.html
Read through the introduction and then click on "Design a Cross Between Two Flies"
Carefully read through the instructions and complete two of the following three crosses. ( Flies with genotype "+" are wild type flies (meaning that they have the phenotype that is most common) Then complete a cross of your own with a trait.
For each of these do the initial cross and then do the F1 cross. Then analyze the F2 offspring. To do so you must figure out the genotypes of the F1 offspring and complete a Punnett Square to determine expected ratios. Then complete the Chi-Square Analysis to determine the accuracy of your Punnett Square Hypothesis. Complete each of the following charts for your crosses.
Cross 1: __________________________________
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Phenotype |
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Complete Punnett Square to show expected outcome ratios (hypothesis) on separate sheet.
Results Including Sex
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Term |
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Degrees of Freedom = Level of Significance = |
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Is this trait inherited as a recessive, dominant or sex-linked allele (circle one)
Cross two __________________________________
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Phenotype |
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Punnett Square with Expected Ratios of Cross (on separate sheet)
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Degrees of Freedom = Level of Significance = |
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Is this trait inherited as a recessive, dominant or sex-linked allele (circle one)
Cross three __________________________________
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Phenotype |
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Punnett Square with Expected Ratios of Cross (Do on separate sheet)
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Numbers |
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Term |
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Degrees of Freedom = Level of Significance = |
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Is this trait inherited as a recessive, dominant or sex-linked allele (circle one)
Questions? Comments
Shannon Tice