1) Do all the possible monohybrid crosses for the ABO blood group and give the genotype and phenotype ratios following each cross. Note: there are 3 alleles for each gene so there are more than six possible crosses, and since A and B are co-dominant, there are more than 2 possible phenotypes in some crosses.
a) List all the possible parent crosses for the ABO blood group. There should be 21 possible crosses.