Blood cell
![Diagram showing the development of different blood cells from haematopoietic stem cells to mature cells.](/Images/godic/202501/16/Hematopoiesis_simple.svg4752.png")
![Red and white human blood cells as seen under a microscope using a blue slide stain](/Images/godic/202501/16/Red_and_white_human_blood_cells_as_seen_under_a_microscope_using_a_blue_slide_stain4753.jpg")
![Scanning electron microscope image of circulating human blood, showing red and white blood cells (a few lymphocytes, monocytes, neutrophils), and disc-shaped platelets](/Images/godic/202501/16/SEM_blood_cells4753.jpg")
![Blood components](/Images/godic/202501/16/Illu_blood_components.svg4753.png")
A blood cell, also called a haematopoietic cell, hemocyte, or hematocyte, is a cell produced through hematopoiesis and found mainly in the blood. In mammals, these fall into three general categories:
Together, these three kinds of blood cells add up to a total 45% of the blood tissue by volume, with the remaining 55% of the volume composed of plasma, the liquid component of blood. The volume percentage of red blood cells in the blood (hematocrit) is measured by centrifuge or flow cytometry and is 45% of cells to total volume in males and 40% in females.