In our bodies, there are three important types of blood cells: red blood cells (RBCs), white blood cells (WBCs), and platelets. White blood cells, or leukocytes, don’t have any color because they lack something called hemoglobin.
Among leukocytes, there are two main types:
Granulocytes: These special cells in our immune system have tiny granules that contain enzymes. They play a big role when we have infections, allergies, or asthma attacks.
Nongranulocytes: Also known as agranulocytes or non-granulocytes, these are another kind of white blood cell called leukocytes.
White blood cells stick around in our lymph system for about 13 to 20 days, and then they move on. In people, the lifespan of a white blood cell is around 13 to 20 days.