ABO identification system is the system of determining the blood type of the Human being by checking the presence of Antigens "A" & "B" on the surface of their RBCs. If A is present, then it is A Blood group, if B, then it is B blood group, if both, then AB and if neither then it is called as O blood group.
Rh Factor is the type by which we classify individuals into two groups - Rh +ve with Rh factor on their surface and Rh - ve, which lacks of it
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