Final answer:
Knowing your blood type is critical for safe blood transfusions, to avoid life-threatening reactions. Type O blood can be used in emergencies for its universal compatibility. Cross-match assays ensure compatibility between donor and recipient blood types.
Step-by-step explanation:
Knowing your blood type is crucial in medical situations, particularly when a blood transfusion is necessary. For instance, if a person requires a transfusion, they must receive blood that matches their own blood type to avoid a possible life-threatening reaction. The major blood types are A, B, AB, and O, based on the presence of specific antigens on the surface of red blood cells (RBCs).
In emergency situations, such as a patient with severe bleeding following an accident, when there is no time to determine the individual's blood type, type O blood is often transfused because it is universally compatible with all other blood types. However, under normal circumstances, cross matching is necessary to ensure compatibility.
If a patient's blood agglutinates with anti-B serum during a typing test, it indicates the presence of B antigens, thus the patient has type B blood. A cross-match assay is performed to ensure the donor's blood is compatible with the recipient's, preventing transfusion-related complicatioon.