Blood is composed of cells suspended in a liquid. These cells – Red blood cells (RBC), White blood cells (WBC), and Platelets – account for 45% of the volume of blood. The remaining liquid portion is the plasma. Each pint of donated blood can be separated into several components to meet the needs of various patients. Therefore every pint (unit) of blood becomes a vast array of life saving products; and there is only one source YOU!
Red Blood Cells transport oxygen to body cells and remove carbon dioxide. Red cells need nourishment for proper functioning. This is supplied through iron rich food like meat, liver, eggs, green leafy vegetables and whole–grain bread. Red cells are produced in the bone marrow, at a normal rate of about 17 million cells per second.
White Blood Cells (leukocytes) are the protective and defensive cells in the blood stream. They attack bacteria by entering capillary walls to reach the area of infection where they destroy bacteria. White blood cells are also made in the bone marrow, and are produced at twice the rate of red blood cells.
Platelets are colorless cells, produced in the bone marrow by the fragments of megakaryocytes. The main function of megakaryocytes is to control bleeding by helping to form wound–healing blood clots. Platelets also take care that blood vessels stay leakproof in daily life. Platelets adhere to torn blood vessels to create a plug, thus slowing the loss of blood.
Plasma is 92% water, 7% protein, 1% minerals, sugar, hormones, and enzymes plus vitamins. Plasma is the source of gamma globulin, serum albumin, fibrinogen and clotting factors. Factor VIII is the valuable clotting factor – a fraction of plasma.