Explain the role played by haemoglobin in the transportation of oxygen and carbon dioxide.
I. Haemoglobin is an iron containing protein is present in the red blood cells (RBC).
II. It is a respiratory pigment that carries oxygen through red blood cells.
III. It transports about 97% of oxygen from lungs to the tissues and in returns it transports carbon dioxide from tissues to the lungs.
IV. Oxygen enters the body in the lungs, where it attaches to haemoglobin and carries blood to the body tissues.
V. In the tissues oxygen is removed from the blood, the blood cells are considered deoxygenated, and they flow back through the heart by veins.
VI. While passing through the body, blood picks up carbon dioxide as waste, which attaches to haemoglobin to form carboxyhaemoglobin.
VII. Carbon dioxide is also transported through blood plasma as bicarbonate(HCO3) ions.
VIII. At the end of the cycle, carbon dioxide passes through the lungs and out of the nose.
