Science -- Your Future, Scotland's Future
SCI-FUN Roadshow Exhibits -- Blood Groups
In this exhibit you learn about the importance of different blood groups in transfusions.

Blood is vital. It takes oxygen and food to our cells and takes away carbon dioxide and other waste products.

Loss of blood through injury can make us quite unwell. Blood-loss will make us feel dizzy, tired and confused; it can even cause shock which can be fatal. This is because a lack of blood means that people's cells can't get enough food and oxygen.

To treat blood-loss in patients, we replace their blood. We get this blood through donation: adults can donate around 500 mL of their own blood every 4-5 months to be given to a patient in need. Blood is given to patients who have lost blood due to injury, and also to patients during surgery, as a lot of blood is lost then.

But people have different types of blood, called Blood Groups. If you give somebody the wrong blood, their immune system will destroy the donated blood. Sometimes this can cause kidney failure and death.

Blood groups are due to proteins and other substances stuck to the surface of the red blood cells. The immune system can recognise when a red blood cell has a surface substances that is not normally on the body's red blood cells, and thinks that the cell must be dangerous, so destroys it.

Blood of the same group has the same substances on the red blood cells, so the immune system doesn't recognise that it comes from elsewhere. The two most well known kinds of blood grouping are ABO blood grouping and Rhesus blood grouping.

ABO blood grouping depends on carbohydrates on the blood cells. There are two kinds of carbohydrates, A and B. Cells can have A (blood group A), B (B), neither (O) or both (AB). Since O red blood cells have no carbohydrate on their surface, they aren't recognised by anyone's immune system, so anyone can receive a donation of O blood. And since AB has both carbohydrates, AB people's immune system don't recognise either, so they can receive a donation of anyone's blood.

There are two Rhesus blood groups, Rh+ and Rh-. Rh+ blood has Rhesus factor on its surface, and Rh- blood does not. Rh+ people can receive Rh- blood, but Rh- people cannot receive Rh+ blood.

There are many other types of blood grouping, but these are much more rare.

1 Blood takes ________ and food to our ________.
2 How would blood-loss make you feel?
3 How often can adults donate blood?
4 What will the immune system do to the wrong blood?
5 What are the two most well known kinds of blood grouping?
6 If someone is blood group B Rh+, what kinds of blood can they receive and who can they donate their blood to?

1 Do you know your blood group? Try to find out the blood groups of your family. Make a family tree showing everybody's blood group.
2 Learn about how to carry out First Aid for blood-loss. A First Aid course will teach you what to do if someone is bleeding, and how to treat shock (a conditon caused by blood-loss). See if you can enrol on a course, or if your school or youth group could organise one. With this knowledge, you could save someone’s life.