The decline in the occurrence of sickle-cell anemia in the American population is most likely the result
of
a. a lower mutation rate in the United States than in Africa.
b. the advantage of both homozygous forms over the heterozygous form.
c. the development of appropriate medical treatment for the sickle-cell condition in the
United States.
d. a decline in the occurrence of malaria in the United States.
e. the absence of mosquitoes.
D
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Eight 10-year-olds in the community became sick within a 24-hour period with vomiting and diarrhea. Personnel from the health department interviewed the children and their families, attempting to determine the source of the illness. Which piece of information below is most suggestive of the common source?
A. All eight children attended the same birthday party two days prior to becoming ill. B. Five of the eight children ride the same school bus. C. In two of the eight families, siblings were just beginning to show signs of illness at the time of the interview. D. All eight children go to the same school. E. Six of the eight children are on the same soccer team which practices three times/week.
The evolution of horses is best characterized as
a. a linear sequence of intermediate forms leading to modern horses. b. an example of evolutionary convergence. c. poorly documented and speculative. d. a gradual increase in body size. e. a complex branched history with many extinct lineages.
Which is an example of subfunctionalization of a gene duplicate?
A. Gene duplication leads to new combinations of existing exons, as in the jingwei locus B. A duplicate of a metabolic gene evolves to work as an antifreeze protein in an Arctic fish. C. Retrotransposition of the Alu elements into many positions in the genome D. Duplication of hemoglobin genes allows specialized versions to be expressed in fetus vs. adult. E. A gene is duplicated to a new position in the genome, but its regulatory elements are missing, so it is never expressed.
Describe how comparative genomics is aiding in the discovery and treatment of human disease
What will be an ideal response?