Guide To Understanding The Different Blood Types

Blood is made up of red blood cells, white blood cells, platelets, and plasma. Markers called antigens are found on the surface of red blood cells, and differences in these markers classify various blood types. There are thirty-five different systems of blood group classification. Currently, blood is primarily categorized according to its ABO group and the presence or absence of the Rh factor. The blood type a child has is determined by genetics. Doctors mix a patient's blood sample with different substances to see how the blood reacts to reveal an individual's blood type. Blood typing tests are normally performed at birth. Patients are also tested before blood donation.