Question

Explain the role of haemoglobin in the transport of gasses during respiration

Answer 1

We take in oxygen during inhalation and it reaches lungs through respiratory tract. Hemoglobin, an intracellular protein is the primary vehicle for transporting 97% of oxygen in the blood. 3% of Oxygen is carried by plasma. Hemoglobin is contained in erythrocytes.
The amount of oxygen bound to the hemoglobin at any time is related to the partial pressure of oxygen to which the hemoglobin is exposed. In the lungs, at the alveolar-capillary interface, the partial pressure of oxygen is high, and therefore the oxygen binds readily to hemoglobin. As the blood circulates to other body tissue in which the partial pressure of oxygen is less, the hemoglobin releases the oxygen into the tissue because the hemoglobin cannot maintain its full bound capacity of oxygen in the presence of lower oxygen partial pressures.
Red blood cells in the blood are flattened disc like structures responsible of transporting oxygen and carbon dioxide gases. Red blood cells consist of red iron-containing pigment called as haemoglobin. Haemoglobin is a respiratory pigment that carries oxygen through red blood cells. Oxygenated blood is carried to tissues.
The exchange of gases at tissue level is called as peripheral gas exchange. The capillaries of circulatory system deliver the oxygen rich blood to the tissues of the body. This oxygen diffuses across the walls of the capillaries into tissues. In turn carbon dioxide diffuses into the blood from tissues. The carbon dioxide diffused into the blood binds to haemoglobin present in the blood to form carboxyhaemoglobin. This de-oxygenated blood is carried to lungs for purification. In the lungs, carbon dioxide from carboxyhaemoglobin dissociates leaving behind haemoglobin. The cycle continues to cary oxygen from lungs to tissues and carbon dioxide from tissues to lungs by haemoglobin.