The red blood cells in the blood bind oxygen to the red blood pigment
(= hemoglobin) which they contain. In this manner, the oxygen from the lungs is transported to all parts of the body (= oxygen transport). The blood contains about 4-5 billion (!) Red blood cells per ml. Red blood cells are always prepared fresh in the red bone marrow, by division of certain bone marrow stem cells (= erythroblasts).
The blood contains three different types of cells:
- Red blood cells.
- White blood cells (= leukocytes) are closely involved in the immune response of the body against infection by micro-organisms (including bacteria, viruses and fungi).
- Platelets (= thrombocytes) initiate the blood coagulation that stops the bleeding after a damage.