Blood cells

A blood cell, also called a haematopoietic cell, hemocyte, or hematocyte, is a cell produced through hematopoiesis and found mainly in the blood.

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 () is measured by centrifuge or flow cytometry and is 45% of cells to total volume in males and 40% in females.

Haemoglobin (the main component of red blood cells) is an iron-containing protein that facilitates transportation of oxygen from the lungs to tissues and carbon dioxide from tissues to the lungs.

Red blood cells or erythrocytes, primarily carry oxygen and collect carbon dioxide through the use of haemoglobin, and have a lifetime of about 120 days. In the process of being formed they go through a unipotent stem cell stage. They have the job alongside the white blood cells of protecting the healthy cells.

RBCs are formed in the red bone marrow in the adults. After the completion of their lifespan, they are destroyed in the spleen.

White blood cells or leukocytes, are cells of the immune system involved in defending the body against both infectious disease and foreign materials. Five diverse types of leukocytes exist, and are all produced and derived from multipotent cells in the bone marrow known as a hematopoietic stem cells. They live for about 3 to 4 days in the average human body. Leukocytes are found throughout the body, including the blood and lymphatic system.

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