Question

How is the sickle-cell allele maintained through natural selection?


a. Individuals with two recessive alleles have very high rates of reproduction.


b. Mosquitoes that pass along the parasite also pass on the recessive allele.


c. Individuals with two dominant alleles have very low rates of reproduction.


d. Heterozygous individuals pass the dominant and recessive alleles to offspring.

Answer 1

heterozygous individuals pass the dominant and recessive alleles to offspring

Answer 2

• Heterozygous individuals pass the dominant and recessive alleles to their offspring. The heterozygous condition restricts the effect of malaria in our body, especially in children.

So, the ones who go through this condition would tend to have more chances in surviving in a malaria affected country, some of whose children would inherit the trait.

The blood of a carrier is changed by the latent allele, causing increased surface tension that makes it difficult for malaria to enter the cell.