Blood Transfusion

Replacelment of loss or diseased blood using donor blood is called blood transfusion.
ABO system of blood were discovered by K.Landteiner in 1900.
An antigen called "A" is seen on the surface of RBC's and an antibody "B" is seen in the plasma in some people and they are said to be belonging to "A" blood group.
If "B" antigen is seen on the surface of RBC's 'a' antibody is seen in the plasma it is "B" group.
If both a and b antigens are present on RBC's no antibody is seen in plasma, it s "AB" group.
if no antigen is seen on the surface of RBC's but a and b antigen are seen in the plasma it s "O" group.

"AB" blood group is universal recipient "O" is universal donor.
"A" gp blood can be given to a and ab gp.
"B" gp blood can be given to b and ab.
ab gp can be given to ab only.
o gp blood can be given to all.