Describe the role of haemoglobin in transport of oxygen and carbon dioxide in the body?

              Transport of Oxygen

• Oxygen binds with haemoglobin to form oxyhaemoglobin.

• 1 molecule of haemoglobin carries 4 molecules of oxygen.

• Formation of oxyhaemoglobin depends upon − pO₂, pCO₂, pH, temperature

• In alveoli − pO₂ (high), pCO₂ (low), pH (high) temperature (low)
  Hence, oxyhaemoglobin forms.

• In tissues − pO₂ (low), pCO₂ (high), pH (low) temperature (high)
  Hence, oxyhaemoglobin dissociates.
  
  Transport of Carbon Dioxide

• CO₂ is carried as carbamino-haemoglobin by blood.

• When pCO₂ (high), pO₂ (low) − binding of CO₂ occurs (as in tissues)

• When pCO₂ (low), pO₂ (high) − dissociation of CO₂ occurs (as in alveoli)

• CO₂ is bound with haemoglobin in tissue and dissociates in alveoli where it is released.