What would happen to the HS allele if a vaccine for malaria was 100% effective?
The human ?-globin gene has two alleles, HS and HA, individuals that are homozygous for HS have sickle-cell anemia and a lower fitness. Individuals that are heterozygotes (HSHA) do not show sickle-cell symptoms and have a resistance to malaria. Individuals that are homozygous for HA have the highest fitness but are susceptible to malaria.
. The HS allele would increase in frequency in populations where malaria was present.
B. The HS allele would decrease in frequency in populations where malaria was present.
C. There would be no change in frequency between the HS and HA allele.
D. Negative frequency-dependent selection would occur and there would be a balanced frequency between the two alleles.
E. The frequency of homozygous individuals would decrease and the heterozygous individuals would increase.
B. The HS allele would decrease in frequency in populations where malaria was present.
You might also like to view...
Which one of the following proteins is not required at low, basal levels for the regulation of the expression of the lac operon?
A. thiogalactoside transacetylase B. galactoside permease C. ?-galactosidase
The gene that is disrupted to cause Basal Cell Nevus Syndrome in humans is closely related to a gene in a species of fruit fly. What does this tell you about the diversity of life-forms on the planet and their origin? What does this tell you about the importance of understanding the genetic makeup of all organisms?
What will be an ideal response?
Refer to Figure 15-1. The use of antibiotic medium at the end of this process:
a. selects against plasmids containing human DNA fragments.
b. selects for plasmids containing particular DNA fragments.
c. selects for bacteria containing plasmids.
d. selects for bacteria lacking plasmids.
e. prevents contamination of the medium
Look at the accompanying figure. In Step 1 ________ ions enter the neuron, while in Step 2 ________ ions leave the neuron
Fill in the blank(s) with correct word