Question

21.Sometimes a gene which carries a major disadvantage in homozygous condition confers an advantage in heterozygous condition. Explain by giving the suitable example.

Answer 1

this can be explained by taking example of sickle cell anaemia.

if genes for this disease are present in homozygous condition (Hbs hbs)

they can cause death of individual.

but in heterozygous condition they provide a special advantage .

individual which is heterozygous for this trait (Hba hbs) cannot suffer malaria.

hope this will help