What determines a person's blood type?

The presence or absence of specific proteins (antigens) on the surface of their red blood cells.

Explain why a person with type AB blood is considered a universal recipient.

Type AB blood has both A and B antigens and no antibodies, so they can receive blood from any ABO blood type without rejection.

No antigens; Anti-A and Anti-B antibodies

I can explain how different blood groups are determined by antigens and antibodies.

1
Blood types are determined by the presence of specific proteins, also known as antigens, on the surface of red blood cells (erythrocytes).
2
Type A blood has A proteins and anti-B antibodies, while type B blood has B proteins and anti-A antibodies.
3
A person with type O-negative blood is considered a universal donor because their blood lacks A, B, and Rh antigens, while a person with type AB-positive blood is considered a universal recipient.