Which blood group is known as the universal donor because red blood cells from this group lack major A and B antigens?

💡 Solution & Explanation

Group O negative red blood cells lack A, B, and Rhesus antigens on their surface, preventing immune system recognition and severe agglutination reactions when transfused into recipients of other blood groups. Individuals with AB positive blood group are conversely termed universal recipients because their plasma lacks antibodies against A and B antigens. Blood grouping based on the ABO and Rh systems was discovered by Karl Landsteiner.