Types of Blood
The ABO System
The type of blood is determined by the form of antigens on the surface of red blood cells. While there are many classification systems, only two of them are widely used: the ABO and the Rh factor system.
Based on the ABO system, blood can be divided into 4 main types:
– Type A contains the A antigen
– Type B contains the B antigen
– Type AB contains both the A antigen and B antigen
– Type O contains no antigen A and no antigen B [2]
