Did You Know!

Human blood is categorized into different groups based on the presence or absence of specific antigens on the surface of red blood cells. The most well-known blood group system is the ABO system, which includes four main blood types: A, B, AB, and O. Each type can be positive or negative depending on the presence of the Rh factor, another important antigen. Blood type compatibility is crucial for blood transfusions to prevent adverse reactions.