Which blood type is the universal donor for red blood cells?

Which blood type is the universal donor for red blood cells?

• A. O Negative
• B. A Positive
• C. AB Positive
• D. B Negative

Answer: (A)

Universal donor for red blood cells means donor cells that can be given to anyone without triggering an immune reaction. This requires red cells that lack A and B antigens as well as the Rh D antigen. Type O negative fits this perfectly because its red blood cells have no A or B antigens and are Rh negative. That combination makes it compatible with recipients of any ABO/Rh type, which is why it’s used in emergencies when the patient’s blood type is unknown. Other blood types carry A or B antigens or the Rh antigen, so they can cause reactions in recipients who don’t have those antigens and aren’t universally compatible.

Universal donor for red blood cells means donor cells that can be given to anyone without triggering an immune reaction. This requires red cells that lack A and B antigens as well as the Rh D antigen. Type O negative fits this perfectly because its red blood cells have no A or B antigens and are Rh negative. That combination makes it compatible with recipients of any ABO/Rh type, which is why it’s used in emergencies when the patient’s blood type is unknown. Other blood types carry A or B antigens or the Rh antigen, so they can cause reactions in recipients who don’t have those antigens and aren’t universally compatible.