Contrary to their name, white blood cells are colorless, but they can appear as a very light purple to pink color when examined under a microscope and colored with dye. These extremely tiny cells have a round shape with a distinct center membrane (nucleus).
White blood cells, also known as leukocytes, are essential for your body's immune system, protecting you from infection. They are one of the four main components of blood, alongside plasma, red blood cells, and platelets.
While they appear colorless in your body, they can be stained with dyes to make them visible for examination under a microscope.
