Individuals with type O blood are
often called universal donors, and those with
type AB blood are called universal recipients.
Blood group O Individuals do not have either A
or B antigens on the surface of their RBCs, and
their blood serum contains IGM anti-A and anti-
B antibodies. Therefore, a group O individual
can receive blood only from a group O
individual, but can donate blood to individuals
of any ABO blood group (Le., A, B, O or AB).