Two different antigen molecules that occuron the surface of blood


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Two different antigen molecules that occuron the surface of blood cells of wild-type mice areproduced through this biosynthetic pathway. Mice that are homozygousfor null mutations in the gene that encodes enzyme A (genotype aa) don’t makeeither antigen 1 or antigen 2. Mice that are homozygous for null mutationsin the gene that encodes enzyme B (genotype bb) don’t make antigen 1. Mice that are homozygous for null mutationsin the gene that encodes enzyme C (genotype cc) don’t make antigen 2. All three genes are unlinked. Two differentantigen molecules that occur on the surface of blood cells of wild-type miceare produced through this biosynthetic pathway. Mice that arehomozygous for null mutations in the gene that encodes enzyme A (genotype aa)don’t make either antigen 1 or antigen 2. Mice that are homozygous fornull mutations in the gene that encodes enzyme B (genotype bb) don’tmake antigen 1. Mice that are homozygous for null mutations in the genethat encodes enzyme C (genotype cc) don’t make antigen 2. Allthree genes are unlinked. Two differenttrue-breeding strains of mice have been isolated that don’t make either antigen1 or antigen 2. When an individual from one strain is crossed with anindividual from the other strain, all of the F1 mice produce bothantigens. PartA What are thecomplete genotypes of the two parental strains? 1) AABBCC 2) AAbbCC 3) AABBcc 4) AAbbcc 5) aaBBCC 6) aaBBcc 7) aabbCC 8) Aabbcc Part B Twoof the F1 mice are crossed toone another. What proportion of the F2 progeny will produce bothantigen 1 and antigen 2? Enteryour answer as a fraction. PartC If F1 mice are crossed to one another, what proportion of the F2progeny would be expected to produce antigen 1, but not antigen 2?Enter youranswer as a fraction. Part D If F1 mice are crossed to one another, what proportion ofthe F2 progeny would be expected to produce antigen 2, but not antigen 1? Enteryour answer as a fraction. PartE If F1 mice are crossed to one another, what proportion of the F2progeny would be expected to produce neither antigen 1 nor antigen 2?Enter your answer as a fraction. PartF Among the F2 progeny, there will be miceof several different genotypes that are phenotypically antigen 1–and antigen 2–. If you wanted to use a testcross in order to test whether any individual F2mouse that doesn’t produce either antigen is defective in the production ofenzyme A, what would be the best genotype for the tester mouse? List the genein your answer in alphabetical order with no spaces between them. Forexample: DDEEFF, DdEdFf, ddeeff, etc. ATTACHMENT PREVIEW Download attachment Q4 .docx Two different antigen molecules that occur on the surface of blood cells of wild-type mice are produced through this biosynthetic pathway. Mice that are homozygous for null mutations in the gene that encodes enzyme A (genotype aa) don’t make either antigen 1 or antigen 2. Mice that are homozygous for null mutations in the gene that encodes enzyme B (genotype bb) don’t make antigen 1. Mice that are homozygous for null mutations in the gene that encodes enzyme C (genotype cc) don’t make antigen 2. All three genes are unlinked. Part A What are the complete genotypes of the two parental strains? 1) 2) 3) 4) 5) 6) 7) 8) AABBCC AAbbCC AABBcc AAbbcc aaBBCC aaBBcc aabbCC Aabbcc Part B Two of the F1 mice are crossed to one another. What proportion of the F 2 progeny will produce both antigen 1 and antigen 2? Enter your answer as a fraction. Part C If F1 mice are crossed to one another, what proportion of the F 2 progeny would be expected to produce antigen 1, but not antigen 2?Enter your answer as a fraction. Part D If F1 mice are crossed to one another, what proportion of the F2 progeny would be expected to produce antigen 2, but not antigen 1? Enter your answer as a fraction. Part E If F1 mice are crossed to one another, what proportion of the F 2 progeny would be expected to produce neither antigen 1 nor antigen 2?Enter your answer as a fraction. Part F Among the F2

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