Though sickle cell anemia is frequently lethal for individuals who are homozygous for the sickle cell allele, natural selection seems to have maintained that allele in certain geographic locations.A likely explanation for this observation is
A)the forward mutation rate to sickle cell is much higher in those regions.
B)individuals with sickle cell anemia live longer and have more children.
C)reversion from sickle cell to wild type is prevented in some populations.
D)individuals who are heterozygous for the sickle cell allele are protected from malaria.
E)only certain populations have been tested for the presence of the sickle cell allele.

Question

Quizplus · Accepted Answer

Individuals who are heterozygous for the sickle cell allele (carrying one copy of the sickle cell allele and one copy of the normal allele) are known to be more resistant to malaria. This is because the sickle cell allele affects the shape of red blood cells, making it harder for the malaria parasite to infect and replicate within these cells. Therefore, in regions where malaria is prevalent, individuals who carry one copy of the sickle cell allele are more likely to survive and pass on this allele to their offspring, maintaining it in the population. This phenomenon is known as balancing selection.

Though Sickle Cell Anemia Is Frequently Lethal for Individuals Who