Blood is made up of three parts: red cells, white cells and platelets. Red blood cells are responsible for the oxygen delivery from the lungs to the tissue in the body. White blood cells are a part of the immune system. These components circulate in the fluids in the blood vessels, which is pumped by the heart. Although each of these components circulate side-by-side, they have different responsibilities in the body.
Red cells, or hemoglobin, are responsible for delivering oxygen to the tissue. The red blood cells are sent to the lungs, where oxygen is picked up in the capillaries surrounding the lungs' alveoli. The oxygen is bonded to the red blood cell and returned to the heart. The heart pumps the blood through the arteries to tissue cells in the body. The oxygen is dropped off in the cells, and the deoxygenated red blood cell is returned to the heart through the veins.
White Blood Cells
White blood cells are the immune system's defenses against invading organisms such as bacteria or viruses. Unlike red blood cells which are only composed of hemoglobin, white blood cells have several types. T cells and macrophages are the killer cells that destroy microbes upon discovery. B cells are responsible for the immune system's "memory." B cells are responsible for antibody creation.
Antibodies are the proteins of the immune system that circulate in the blood and attach to invaders. They are produced by the white B cells. Antibodies make microbes like bacteria or viruses easier to identify and destroy by macrophages and T cells. Antibodies are specific to cell surface proteins on the invading microbe, which is why new ones are created each time a new bacteria or virus is discovered in the body.
Bone marrow is a spongy tissue that is located within the hardened bone. It is the source of creation of new red and white blood cells. The process of creating new blood cells is called hematopoiesis. The cells created by hematopoiesis are stem cells, which are undifferentiated cells. Undifferentiated means the cell does not have a "decided" function, so they can mature into any type of cell. Undifferentiated stem cells are the focus of many therapeutic remedies for degenerative diseases.
Complete Blood Count (CBC)
When a patient goes for diagnosis of a blood disorder, the physician may take a CBC. This procedure takes a total count of the blood cells in the plasma. A low red blood cell count indicates anemia. High white cell counts can indicate the body is fighting disease. High white blood counts that do not lower after disease has been eliminated from the body can indicate possible leukemia.