Our body needs a constant supply of blood. The blood contains haemoglobin which is a respiratory pigment and a conjugated protein. It contains iron and globin protein. This iron-containing pigment supplies more oxygen to the tissues and gives red colour to the blood. The deficiency of iron or this haemoglobin pigment in the blood leads to anaemia. The iron pigment or haem pigment of haemoglobin increases the carrying capacity of oxygen. Our body tissue needs oxygen for metabolism.We get iron from foods and these irons play an important role in RBC production in the bone marrow.
In cells use oxygen to release energy stored in sugars such as glucose. In fact, most of the energy used by the cells in your body is provided by cellular respiration.