White blood cells are much fewer than red blood cells. There are about 700 red blood cells for every white blood cell. White blood cells have cell nuclei; are the body's protection from infection and disease and consist of lymphocytes and monocytes with relatively clear cell plasma, and three types of granulocytes , whose plasma is filled with granules.

Leukopenia is a disease symptom defined as a lower than normal number of white blood cells in the blood. Too few white blood cells means the body cannot fight infection. Leukocytosis refers to an increase in the number of white blood cells in the blood. This increase can be from many things but is usually indicative of an infection of some sort. Leukemia and lymphoma are two types of cancer in which white blood cells multiply out of control. When there are too many cells present, the bone marrow cannot produce other types of blood cells and the body cannot operate efficiently.

White Blood Cells Development