B: This blood type has the B antigen on the surface of its red blood cells.
AB: This blood type has both the A and B antigens on the surface of its red blood cells.
O: This blood type has neither the A nor the B antigen on the surface of its red blood cells.
In addition to the ABO blood group system, there are also other blood group systems, such as the Rh system. The Rh system is based on the presence or absence of the Rh factor on the surface of red blood cells. People who have the Rh factor are Rh-positive, while those who do not have the Rh factor are Rh-negative.
