Why do individuals who are heterozygous for sickle cell anemia have a resistance to malaria? A)formation of hemoglobin aggregates makes red blood cells impervious to parasitic infection B)shortened life span of red blood cells does not allow sufficient time for the parasite to mature in the red blood cell C)diminished blood flow to the skin as a result of sickled red blood cells blocking capillaries prevents mosquitoes from actually transferring the malaria parasite to individuals D)sickle cell hemoglobin fibers have both decreased O₂ and CO₂ carrying capacity; since CO₂ is a mosquito attractant, diminished CO₂ exhalation does not attract mosquitoes E)none of the above

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Individuals who are heterozygous for sickle cell anemia have both normal hemoglobin and sickle cell hemoglobin. The sickle cell hemoglobin causes red blood cells to take a sickle shape and have a shortened lifespan, which limits the amount of time the malaria parasite has to multiply and cause symptoms. This provides a selective advantage against malaria, leading to a higher frequency of sickle cell carriers in regions where malaria is endemic.

Why Do Individuals Who Are Heterozygous for Sickle Cell Anemia