Blood groups has some secrets in it, genetically inherited from generation to generation. However blood groups are normally grouped or classified according to the presence of particular molecules (antigen and antibodies)


According to the presence and absence of antigen and antibody molecules, blood groups are classified into four main groups called A,B,AB and O types.


The antigens are present on the surface of the red blood cells(RBC).


The antibodies are present in the blood plasma.

Blood groups AntigenAntibodies
AA – antigenanti – B
BB – antigenanti – A
ABA and B antigennone
Ononeanti A and anti -B

Rhesus(Rh) factor is another important factor in classification of the blood groups. Rh factor is the RhD antigen present in the red blood cells.


Mainly they are Rh positive(+ve) – presence of RhD ANTIGEN and Rh negative types(-ve) – absence of RhD ANTIGEN.


Every blood group has either Rh (+ve) or Rh (-ve). so now we have about eight different types of blood groups.


Every individual has one blood type of the eight groups with Rh +ve or -ve. For example, O-blood group can be seen as O(+ve) OR O(-ve)


Blood can be transferred from one person to other by process called Blood transfusion. Blood transfusion are mainly done intravenously.


According to the antigen, antibodies and Rh factors, blood transfusion has more restrictions.


person who donates blood are called as DONORS and person who receives blood are called as RECIPIENT


Not every blood donated can be transferred to every one. Only after analyzing blood for matching transfusion can be done.


Let us see the matching group of blood groups suitable for successful transfusion


The chart of blood groups from whom you can receive the blood is given below.

If YourBlood GroupisO-O+B-B+A-A+AB-AB+
Now its clear that AB+ve is the universal recipient and O-ve is the universal donor. But AB+ve can donate blood only to AB+ve and O-ve can receive blood only from O-ve.

Below we can see the percentages of blood groups spread among people across the world.

Blood type and RhHow many people have it?
O +40 %
O –7 %
A +34 %
A –6 %
B +8 %
B –1 %
AB +3 %
AB –1 %