Question: what is white blood cells and what they do for our body?

Edward Codling answered on 13 Jun 2011:

I am not an expert on this topic but I’ll have a go at answering!

Blood is made up of three things:

1. Plasma (a watery like substance) which acts as the liquid that carries the other cells around.
2. Red blood cells – these are the cells that carry oxygen around the body so that you can do normal functions like moving around.
3. White blood cells – these are the defence mechanism of the body.

The white blood cells patrol around the body looking for ‘foreign objects’ that they don’t recognise as being from your body. These can be things like bacteria or viruses or even objects like splinters or grit. The white blood cells then surround the object and kill it (if it is a bacteria cell or virus).

When you have a cut or a spot and it gets infected most of the ‘pus’ that you see is actually dead white blood cells that have attacked the infection.

It is a fascinating system to study but people can have serious problems when there is an imbalance in the number of white (or red) bllod cells in their body. Sometimes, the white blood cells can also start to attack the host body in mistake – this then leads to serious diseases and problems.

In most people there is usually no problem though so don’t worry!