Explain transport of oxygen ( class …

Transport of oxygen

• Haemoglobin is a red coloured iron containing pigment present in the RBCs.
• O₂ can bind with haemoglobin in a reversible manner to form oxyhaemoglobin.
• Binding of oxygen with haemoglobin is primarily related to partial pressure of O₂ and partial pressure of CO2, hydrogen ion concentration and temperature are the other factors which can interfere with this binding.
• A sigmoid curve is obtained when percentage saturation of haemoglobin with O₂ is plotted against the pO₂ and the curve is called the oxygen dissociation curve.
• pCO2, H⁺ concentration have effect on binding of O₂ with haemoglobin.
• In the alveoli, where there is high pO₂, low pCO₂, lesser H⁺ concentration and lower temperature, the factors are all favourable for the formation of oxyhaemoglobin, and where low pO₂, high pCO₂, high H⁺ concentration and higher temperature exist, the conditions are favourable for dissociation of oxygen from the oxyhaemoglobin.
• Every 100 ml of oxygenated blood can deliver around 5 ml of O₂ and each haemoglobin molecule can carry a maximum of four molecules of O₂.