Differentiate between incomplete and co-dominance
Incomplete dominance: In the four Oclock plantMirabilis jalapa, when a homozygous red flowered plant (RR) is crossed to a homozygous white flowered plant, all flowers in the F1 are pink. When F1 plants are self pollinated, the phenotypic ratio is found to be 1 : 2 : 1. The heterozygous (Rr) plants have an intermediate colour pink.
Co-dominance - The four blood groups of humans are determined by a single gene. The alleles IAfor A group, IB for B blood group are both dominant. Therefore person with alleles IA and IB has the blood group AB as both the genes IA and IB are co-dominant. The gene i when homozygous (ii) gives the blood group O.