Scientists have concluded that the AS genotype as an adaptation for survival in Africa. Support the conclusion in terms of natural selection A. The frequency of the AS allele increases proportionately to the number of Africans in the population B. Because Malaria does not exist in the U.S and the AS allele does not provide any advantage to survival there.C. As the frequency of Malaria increases so does the frequency of the AS allele combination as it protects against getting MalariaD. Those without the AS genotype die out due to sickle cell disease; the populations left with a greater allelic frequency of the AS genotype Sickle cell anemia is the result of the mutation of a single DNA nucleotide onchromosome 11. The mutation changes the chemical properties of hemoglobin, theiron- protein complex that carries oxygen within red blood cells. Sickle cell anemiais caused by a point mutation in the B globin gene. There are two globin allelesimportant for the inheritance of sickle cell anemia: A and S. Individuals with twonormal A alleles (AA) have normal hemoglobin and normal red blood cells. Peoplewith two S alleles (SS) develop sickle cell anemia. Those who are heterozygous forthe sickle cell allele (AS) produce both normal and abnormal hemoglobin.Heterozygous individuals are usually healthy, but they may suffer some symptomsof sickle cell anemia under conditions of low blood oxygen, such as high elevation.Heterozygous (AS) individuals are said to be carriers of the sickle cell trait. In theU.S. about 1 in 500 African-Americans develops sickle cell anemia. In Africa, about 1in 100 individuals develop the disease. The frequency of this potentially fataldisease is much higher in Africa because of the widespread presence of malaria.When malarial parasites invade the bloodstream, the red cells that containdefective hemoglobin become sickled and die, trapping the parasites inside themand reducing infection. Compared to AS heterozygotes, people with the AAgenotype have a greater risk of dying from malaria.Scientists have concluded that the AS genotype as an adaptation for survival inAfrica. Support that conclusion in terms of natural selection.

The carriers of Sickle cell anaemia Trait have resistance against the fatal malaria which is caused.…

Scientists have concluded that the AS genotype as an adaptation for survival in Africa. Support the conclusion in terms of natural selection A. The frequency of the AS allele increases proportionately to the number of Africans in the population B. Because Malaria does not exist in the U.S and the AS allele does not provide any advantage to survival there. C. As the frequency of Malaria increases so does the frequency of the AS allele combination as it protects against getting Malaria D. Those without the AS genotype die out due to sickle cell disease; the populations left with a greater allelic frequency of the AS genotype

Scientists have concluded that the AS genotype as an adaptation for survival in Africa. Support the conclusion in terms of natural selection A. The frequency of the AS allele increases proportionately to the number of Africans in the population B. Because Malaria does not exist in the U.S and the AS allele does not provide any advantage to survival there. C. As the frequency of Malaria increases so does the frequency of the AS allele combination as it protects against getting Malaria D. Those without the AS genotype die out due to sickle cell disease; the populations left with a greater allelic frequency of the AS genotype

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter11: Genome Alterations: Mutation And Epigenetics

Section: Chapter Questions

Problem 16QP: Familial retinoblastoma, a rare autosomal dominant defect, arose in a large family that had no prior...

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A 30 - year - old woman was undergoing therapy for b-thalassemia,a recessive trait caused by absence of or reduced synthesis ofthe hemoglobin b chain, a subunit of the oxygen-carrying moleculein red blood cells. In this condition, red blood cells are rapidlydestroyed, freeing a large amount of iron, which is deposited in tissuesand organs. The blood transfusions the patient had received every twoor three weeks since the age of 7 to stave off anemia were furtheraggravating iron buildup. Her major organs were showing damage, andshe was in danger of death from cardiac disease. Her physician suggestedthat she consider undergoing a hematopoietic (bone marrow)stem cell transplant (HSCT). Since these stem cells give rise to redblood cells, such a transplant could potentially restore her health. Whilethis might seem like an easy decision, it is not. Advanced cases havea high risk (almost 30 percent) for transplantation-related death. At thispoint, the woman is faced with a difficult and…
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