Question

ABO blood groups is a good example of co-dominance. Justify.

Answer 1

-ABO blood group in humans is contributed by gene 'I' that has 3 alleles 'IA' 'IB' and 'i.'
- Because human beings are diploid each person has two of the three alleles.
- IA and I B produce two different types of sugar while allele i does not produce sugar on the plasma membrane of RBC
- When IA and I B are present they both express their own type of sugar- this is codominance