Question

Explain the phenomenon of multiple alleles and dominance taking abo blood gp as an exampls

Answer 1

multiple allelesim- more than 2allele governing the same character.
The ABo blood group are controlled by the I gene.
The I gene has three allele- IA,IB and i.
IA and IB produce sugars while allele i does not.
since humans are diploid,only two allele can exist at a time.IA and IB are completely dominant over i which codes for o blood group.
when IA and IA orIA and i is present blood group is A
when IB and IB or IB and i is present blood group is B
when i and i is present blood group is O
but when IA and IB is present ,co dominance takes place that is both are expressed together,and the blood group will be- AB.
hope that helps