[问答题]
Sickle cell anaemia is a trait that is inherited in a c
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xv h eak86jb7-(Hb$^S$Hb$^S$ ), homozygous unaffected (Hb$^A$Hb$^A$ ) and heterozygous (Hb$^A$ Hb$^S$ ) for the trait over 50 years in Nigeria, West Africa. Malaria, which is a parasitic disease that infects red blood cells, is prevalent in Nigeria.
1.Using the graph, explain whether the sickle cell trait is likely to be in Hardy Weinberg equilibrium.
2.1Describe the trends observed in the graph.
2.2.Suggest a reason for the trend in heterozygotes found in this malaria infected region of Africa.
3.The frequency of the recessive allele in the population was found to be 0.62, calculate the frequency of the dominant allele in the population.
4.1.Assuming that this population is in Hardy Weinberg equilibrium, predict what would happen to the frequency of recessive alleles in the population over 50 more years.
4.2.Outline a reason for your answer.
5.Explain why, under ‘real world’ conditions, it is difficult for organisms to be in Hardy Weinberg equilibrium.
