What is a Blood Group?
All people belong to one of four inherited blood groups: A, B, AB, and 0. The letters A and B refer to the kind of antigen found on an individual's red blood cells. An antigen is a protein on the cell which triggers an immune response, such as the fomation of antibodies, against the antigens which the red cell lacks. For example, A antigens, when exposed to B antigens, will produce anti-B antibodies.

How is my Blood Group Determined?
You inherit your blood group from your biological parents. This chart shows the potential blood groups you may inherit from your parents.

Parent's Blood Group
Parent #1	AB	AB	AB	AB	B	A	A	O	O	O
Parent #2	AB	B	A	O	B	B	A	B	A	O
Child Group O
Child Group A
Child Group B
Child Group AB

What are the four basic groups in the ABO system and what do the group names mean?
Group A Blood has A antigen on red cells.
Group B Blood has B antigen on red cells.
Group AB Blood has both A and B antigens on red cells. Persons with AB blood are called universal recipients.
Group O Blood has neither A nor B antigens on red cells. Persons with Group O are called universal donors.

What is done to match donated blood with patients who need blood?
Before a transfusion is given, it is important to know which blood group a person has because the blood plasma contains strong antibodies, called anti-A and anti-B, that react against the red cells with A or B antigens.

If anti-A antibody came in contact with A antigen (or if anti-B antibody met B antigen), the result could be a dangerous, possibly fatal, transfusion reaction. To prevent such reactions, Medical Technologists will "crossmatch" your blood with donated blood. A sample of your blood and samples from donated blood are tested to make certain they are compatible.

You're The Doctor Now!

What type of blood group could your patient receive? Remember - you want your patient to get well and not have a negative reaction to the transfusion.

To find out the correct answer, move your mouse over each answer space. The right answer will become visible. To clear the grid, just hit the refresh or reload button on your computer.

Patient Blood Group	1st choice for transfusion	2nd choice for transfusion	3rd choice for transfusion	4th choice for transfusion
A			NONE	NONE
B			NONE	NONE
AB
O		NONE	NONE	NONE

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