Which blood type would have anti-A and anti-B antibodies present in plasma?

Which blood type would have anti-A and anti-B antibodies present in plasma?

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

Answer: (A)

In the ABO system, the antibodies present in plasma correspond to antigens you do not have on your own red blood cells. If your red cells lack both A and B antigens, your immune system makes antibodies against both A and B—these are anti-A and anti-B. That situation is Type O. So the plasma of Type O individuals contains both anti-A and anti-B antibodies. Other types have at least one of the A or B antigens on their red cells, so their plasma does not contain both antibodies: Type A has anti-B antibodies, Type B has anti-A antibodies, and Type AB has neither anti-A nor anti-B antibodies.

In the ABO system, the antibodies present in plasma correspond to antigens you do not have on your own red blood cells. If your red cells lack both A and B antigens, your immune system makes antibodies against both A and B—these are anti-A and anti-B. That situation is Type O. So the plasma of Type O individuals contains both anti-A and anti-B antibodies. Other types have at least one of the A or B antigens on their red cells, so their plasma does not contain both antibodies: Type A has anti-B antibodies, Type B has anti-A antibodies, and Type AB has neither anti-A nor anti-B antibodies.