Read the following statements carefully: (A) The respiratory rhythm centre is located in the pons region of the hindbrain. (B) The enzyme carbonic anhydrase is completely absent in blood plasma. (C) A sigmoid curve is obtained when percentage saturation of haemoglobin with O ₂ is plotted against pO ₂ . (D) Alveoli and their ducts form the respiratory or exchange part of the respiratory system. How many of the above s

Step-by-step solution

Statement (A) is incorrect because the respiratory rhythm centre is located in the medulla region of the hindbrain, whereas the pneumotaxic centre is located in the pons region. Statement (B) is incorrect because while carbonic anhydrase is present in very high concentration in RBCs, minute quantities of the same are also present in the plasma. Statement (C) is correct as the Oxygen Dissociation Curve is highly sigmoid. Statement (D) is correct as the alveoli and their ducts form the respiratory or exchange part of