Which blood type has A antigens and anti-B antibodies?

Which blood type has A antigens and anti-B antibodies?

• A. Type A
• B. Type B
• C. Type AB
• D. Type O

Answer: (A)

ABO blood typing hinges on which antigens sit on the surface of red blood cells and which antibodies are present in plasma. A person with A antigens on their red cells also has anti-B antibodies in their plasma. That combination—A antigens with anti-B antibodies—defines Type A blood. In contrast, Type B would have B antigens and anti-A antibodies; Type AB would display both A and B antigens but have no anti-A or anti-B antibodies; Type O would have neither antigen and would possess both anti-A and anti-B antibodies.

ABO blood typing hinges on which antigens sit on the surface of red blood cells and which antibodies are present in plasma. A person with A antigens on their red cells also has anti-B antibodies in their plasma. That combination—A antigens with anti-B antibodies—defines Type A blood.

In contrast, Type B would have B antigens and anti-A antibodies; Type AB would display both A and B antigens but have no anti-A or anti-B antibodies; Type O would have neither antigen and would possess both anti-A and anti-B antibodies.