12. Analyzing Coat Color Mutants - Wild type gerbils from Arizona, Montana, indiana and Califomia are black. - You have obtained pure-breeding mutant varieties of gerbils that are white or pink from these different places. - You know that each gerbil strain has a mutation in a single autosomal gene. - The table below shows E1 proseny obtained when crossing purebreeding WT and mutants to each other. - Bolded boxes at the top and side indicate the purebreeding parent strains you crossed to each other. - The intersection of these boxes represents the phenotype of the F 1 offspring of a particular cross. For each cross, you can assume 100% of the F1 progeny are of the color indicated. a) What is the purpose of crossing the mutant to wild type (black) and observing F1 progeny phenotypes? b) What is the purpose of crossing the mutants to each other and observing F1 progeny phenotypes? c) Which of the strains cannot be used for the analysis you described in (b)? Why? d) When you cross pure-breeding white from Arizona and indiana to each other, you get black in the F 1 . What does this indicate about the mutations that give rise to white in these 2 strains? e) To further explain your answer in (d), assign genotypes for the cross between the 2 purebreeding strains from Indiana and Arizona and their resulting F 1 . Use the letter A if only alleles of one gene are segregating in the cross, letters A and B if 2 genes are involved, etc. Denote dominant alleles with a capital letter and recessive alleles with a small letter.
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UGC NET Paper 1 Mathematical Reasoning & Aptitude.pdf
12- Analyzing Coat Color Mutants - Wild type gerbils from Arizona- Mon.docx
1. 12. Analyzing Coat Color Mutants - Wild type gerbils from Arizona, Montana, indiana and
Califomia are black. - You have obtained pure-breeding mutant varieties of gerbils that are white
or pink from these different places. - You know that each gerbil strain has a mutation in a single
autosomal gene. - The table below shows E1 proseny obtained when crossing purebreeding WT
and mutants to each other. - Bolded boxes at the top and side indicate the purebreeding parent
strains you crossed to each other. - The intersection of these boxes represents the phenotype of
the F 1 offspring of a particular cross. For each cross, you can assume 100% of the F1 progeny
are of the color indicated. a) What is the purpose of crossing the mutant to wild type (black) and
observing F1 progeny phenotypes? b) What is the purpose of crossing the mutants to each other
and observing F1 progeny phenotypes? c) Which of the strains cannot be used for the analysis
you described in (b)? Why? d) When you cross pure-breeding white from Arizona and indiana to
each other, you get black in the F 1 . What does this indicate about the mutations that give rise to
white in these 2 strains? e) To further explain your answer in (d), assign genotypes for the cross
between the 2 purebreeding strains from Indiana and Arizona and their resulting F 1 . Use the
letter A if only alleles of one gene are segregating in the cross, letters A and B if 2 genes are
involved, etc. Denote dominant alleles with a capital letter and recessive alleles with a small
letter.
