Self-sterility in $Nicotiana$ was reported by:

If a child has $O$ type of blood group and the father has $B$ type,the genotype of the father will be:

If the father gives $I^B$ allele and the mother gives $I^A$ allele,state the genotype and blood group of the offspring.

$A$ child has blood group $O$. If the father has blood group $A$ and mother has blood group $B$,work out the genotypes of the parents and the possible genotypes of the other offspring.

$A$ man with blood group $AB$ marries a woman with $O$ blood group. In this situation,

How many phenotypes and genotypes are possible in $ABO$ blood group systems?