an alternate allele of the hemoglobin gene can cause sickle-cell anemia when a person is homozygous for this a

Question

an alternate allele of the hemoglobin gene can cause sickle-cell anemia when a person is homozygous for this allele, but that a person who is heterozygous for the allele actually can derive a benefit from it--protection from malaria. In the United States, 8 percent of African Americans are carriers for the sickle-cell allele, while in central Africa the figure is 20 percent. What could account for this difference? Assess.

Answer 1

well, evolutionarily, people in africa can benefit more from being a partial carrier of sickle cell anemia, because it's not dangerous when they are heterozygous but it does protect against malaria. Therefore it's beneficial in africa, but in America, malaria is not a threat, so naturally to population of sickle cell carriers is much lower

Answer 2

Sickle cellular anaemia is led to by ability of a illness in the haemoglobin molecule it is stumbled on in the purple blood cells that carry oxygen. Haemoglobin is a protein molecule. It incorporates 4 chains- 2 alpha and a pair of beta chains. Proteins are 'custom made' by ability of the cells by ability of starting to be a member of diverse amino acids in a particular order. The shape of a particular area of DNA in the nucleus of the cellular determines the order wherein amino acids are joined. the only distinction between wide-spread haemoglobin and sickle-cellular haemoglobin is in the two beta chains of the molecule. At a place the place there could desire to be the amino acid 'Glutamic acid' there is the amino acid 'Valine'. this mistake is led to by ability of a 'mutation' or exchange in the form of the DNA that codes for the amino acid 'glutamic acid' Sickle cellular anaemia is led to by ability of a genetic mutation. The defective haemoglobin reasons the purple blood cellular to be sickle-formed incredibly of 'a biconcave disc formed'

Answer 3

Ahh biology.

Answer 4

many african americans have a few "european" ancestors scattered in their family tree.