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#Question id: 15816

You and your lab partner have isolated 20 new mutant yeast strains that are defective in synthesis of threonine, an amino acid. These Thr- mutants do not grow on minimal medium, but they do grow on minimal medium supplemented with threonine. Ten of your Thr- mutants (numbered 1 through 10) were isolated in a strain of mating type a (MAT a). The other 10 Thrmutants (numbered 11 through 20) were isolated in a strain of mating type α (MAT α). You and your lab partner cross each of the MAT a strains to each of the MAT α strains, and you include crosses to the appropriate wild-type strains. Your experimental observations are shown in the table below, where (-) indicates diploids that did not grow on minimal medium and (+) indicates diploids that did grow on minimal medium.

Which mutations do you know to be in the same gene?

#Unit 8. Inheritance Biology
  1. [1, 6, 7, 12, 13, 18] [2, 5, 11, 15, 20] [3, 10, 16] [4, 8, 17, 19]
  2. [1, 2, 5, 12, 13, 18] [3, 6, 11, 15, 20] [4, 8, 10, 16] [7, 17, 19]
  3. [1, 2, 5, 11, 15] [3, 17, 19] [4, 8, 10, 16, 20] [6, 7, 12, 13, 18]
  4. [2, 5, 11, 15, 20] [1, 6, 7, 10, 16] [3, 4, 8, 17, 18] [ 12, 13, 19]
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TLS Online TPP Program

#Question id: 19107

#Unit 8. Inheritance Biology

Assume that mating is random. First, consider an autosomal recessive disease that is usually lethal in childhood, and that has an incidence among newborns of 1/3000.  Perhaps the explanation for the incidence of the disease is heterozygote advantage. How large would this heterozygote advantage have to be (assuming the mutation rate is negligible)? 
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#Question id: 19108

#Unit 8. Inheritance Biology

Assume that mating is random. Colorblindness is an X-linked recessive trait that is found in about 5 percent of males. What fraction of females are heterozygous carriers of the colorblindness allele?
TLS Online TPP Program

#Question id: 19109

#Unit 8. Inheritance Biology

Assume that mating is random. Colorblindness is an X-linked recessive trait that is found in about 5 percent of males. What fraction of females are homozygous for the colorblindness allele?  
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#Question id: 19110

#Unit 8. Inheritance Biology

If the frequency of PKU among newborns is approximately 1/10,000 (when the parents are unrelated). What is the risk of a child with PKU if the parents are siblings?
TLS Online TPP Program

#Question id: 19111

#Unit 8. Inheritance Biology

If the frequency of PKU among newborns is approximately 1/10,000 (when the parents are unrelated). What is the risk of a child with PKU if the parents are uncle and niece?
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#Question id: 19112

#Unit 8. Inheritance Biology

the frequency of PKU among newborns is approximately 1/10,000 (when the parents are unrelated). What is the risk of a child with PKU if the parents are second cousins?