One molecule of oxygen can bind to each heme. The reaction is reversible. Under the conditions of lower temperature, higher pH, and increased oxygen pressure in the capillaries of the lungs, the reaction proceeds to the right. Under the conditions of higher temperature, lower pH, and lower oxygen pressure in the tissues, the reverse reaction is promoted and oxyhemoglobin gives up its oxygen. When the red cells reach the lungs, these reactions are reversed and CO 2 is released to the air of the alveoli.
Anemia has many causes.
One of the most common is an inadequate intake of iron in the diet. Blood Groups Red blood cells have surface antigens that differ between people and that create the so-called blood groups such as the ABO system. Link to a discussion of blood groups. These are responsible for making antibodies. Although bone marrow is the ultimate source of lymphocytes, the lymphocytes that will become T cells migrate from the bone marrow to the thymus where they mature.