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TLS Online TPP Program

#Question id: 11501

According to the endosymbiotic theory of the origin of eukaryotic cells, how did mitochondria originate?

#Unit 9. Diversity of Life Forms
  1. from infoldings of the plasma membrane, coupled with mutations of genes for proteins in energy-transfer reactions
  2. from engulfed, originally free-living prokaryotes
  3. by secondary endosymbiosis
  4. from the nuclear envelope folding outward and forming mitochondrial membranes
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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)? 
TLS Online TPP Program

#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?  
TLS Online TPP Program

#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?
TLS Online TPP Program

#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?