Question

What is the function of a white blood cell?

Answer 1

White blood cells are the defense of your body against diseases.

Explanation:

White blood cells(a.k.a leukocytes) are part of the immune system. They are usually produced in the bone marrow and they circulate in the blood and lymph fluids. There are many types of White blood cells.
Types:
1. Neutrophil- immune defenses
2. Eosinophil-defense against parasites
3. Basophil- inflammatory response
4. Monocyte- immune surveillance
5. lymphocyte-immune response

Sources for more info:
1. http://biology.about.com/od/cellbiology/ss/white-blood-cell.htm