Which blood group system is known for its A, B, AB, and O classifications?

The ABO system is the blood group system characterized by the presence of antigens on the surface of red blood cells, which are classified as A, B, AB, or O. Each classification corresponds to the presence or absence of these specific antigens.

Individuals with type A blood have A antigens, while those with type B have B antigens. Those with AB blood possess both A and B antigens, and individuals with O blood lack both types of antigens. This classification is crucial for blood transfusions, organ transplants, and in pregnancy complications, as incompatible blood types can lead to serious reactions in the recipient's immune system.

The other blood group systems mentioned, such as the Rh system, MNS system, and Lewis system, involve different antigens that are important in various contexts but do not specifically categorize blood into the four classifications of A, B, AB, and O as the ABO system does. Thus, the ABO system is the foundational classification in blood typing, making it essential knowledge in the field of medical laboratory science.