Blood group

The blood group refers to a classification system that categorizes blood based on the presence or absence of specific antigens on the surface of red blood cells. The two most important blood group systems are the ABO system and the Rh system.

1. ABO Blood Group System: This system classifies blood into four main types: A, B, AB, and O. These classifications are based on the presence or absence of two antigens: antigen A and antigen B.
   • Type A blood has antigen A on the surface of red blood cells.
   • Type B blood has antigen B on the surface of red blood cells.
   • Type AB blood has both antigen A and antigen B on the surface of red blood cells.
   • Type O blood has neither antigen A nor antigen B on the surface of red blood cells.
2. Rh Blood Group System: This system determines whether the Rh antigen (also known as the Rh factor) is present on the surface of red blood cells. If the Rh antigen is present, the blood type is classified as Rh-positive (e.g., A+, B+, AB+, O+). If the Rh antigen is absent, the blood type is classified as Rh-negative (e.g., A-, B-, AB-, O-).

Knowing a person’s blood group is crucial for medical purposes, especially for blood transfusions and organ transplants. It ensures compatibility between the donor’s blood and the recipient’s blood, reducing the risk of adverse reactions. Additionally, blood group information is used in prenatal care to prevent Rh incompatibility issues between a mother and her unborn baby.