Discussion%20questions%203%20-%20KEY

Discussion%20questions%203%20-%20KEY - Discussion questions...

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Discussion questions 3 1. In humans, the three alleles I A , I B , and i constitute a multiple allelic series that determines the ABO blood group system. In the following examples, state (yes or no) whether the child mentioned can be produced from the marriage shown for each example. (a) A child with blood group O from marriage of individuals - both parents with blood group A. YES (b) A child with blood group O from marriage of individuals - one parent with blood group A and the other parent with blood group B. NO (c) A child with blood group AB from marriage of individuals - one parent with blood group A and the other parent with blood group O. NO (d) A child with blood group O from marriage of individuals - one parent with blood group AB and the other parent with blood group A. YES (e) A child with blood group A from marriage of individuals - one parent with blood group AB and the other parent with blood group B. YES 2. What is the distinction between incomplete dominance and codominance? In incomplete dominance, the phenotype of the heterozygote lies in the range between the phenotypes of the homozygous genotypes. For example, a cross of homozygous plants with red and white flower color results in plants with pink flowers. In codominance, the phenotype of the heterozygote is a mixture of the phenotypes of both of the corresponding homozygous genotypes. The heterozygous phenotype is not an intermediate of the homozygous genotypes. For example, blood groups in humans. 3. Prototrophic strains of Neurospora can make compound Z from the constituents of minimal medium. Two mutant strains lack the ability to make compound Z. Mutant c can make Z if supplied with X, but not if supplied with Y, while mutant strain d can make Z from either X or Y. Construct the simplest linear pathway of the synthesis of Z from the precursors X and Y, show where the pathway is blocked in mutants c and d . The pathway is Y to X to Z, with d blocking the synthesis of Y, and c the synthesis of X from Y.
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4. Twelve uridine-requiring Neurospora mutants (a l) were isolated after ultraviolet irradiation. Complementation testing was done with the following results, where 0
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Discussion%20questions%203%20-%20KEY - Discussion questions...

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