Blood Types Explained - A, B, AB and O - Red Cross Blood
https://www.redcrossblood.org/donate-blood/blood-types.html
WebThere are four major blood groups determined by the presence or absence of two antigens, A and B, on the surface of red blood cells. In addition to the A and B antigens, there is a protein called the Rh factor, which can be either present (+) or absent (–), creating the 8 most common blood types (A+, A-, B+, B-, O+, O-, AB+, AB-).
DA: 24 PA: 85 MOZ Rank: 12 Up or Down: Up