Question

What's the role of all the different blood groups what's the difference ?

Answer 1

Karl Lanchaister discovered the concept of blood goups. He found that the human RBCs came with certain proteins called antigens, he found that there were two antigens A and B. However he also discovered that the plasma also contained complimentary antibodies.

So the person whose RBCs have antigen A belong to blood group A and those with antigen B belong to blood group B and those who have both belong to AB and those with none belong to O (it actually represents 0).

Now A can give blood to A but it cannot give to B because of the presence of antibodies similarly B can give to B but not to A. AB can accept blood from any blood group because of absence of antibodies. Whereas O contains only antibodies so it can accept blood only from O but can give to anyone.

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