Which of the following statements are not correct for transport of oxygen?

(i) About 97 per cent of O 2 is transported by RBCs in the blood.

(ii) Each hemoglobin molecule can carry a maximum of four molecules of O 2 .

(iii) Binding of oxygen with hemoglobin is primarily related to partial pressure of O 2 .

(iv) Partial pressure of CO 2, hydrogen ion concentration and temperature are the other factors which can interfere with this binding.

(v) A sigmoid curve is obtained when percentage saturation of hemoglobin with O 2 is plotted against the

(vi) Every 100 ml of oxygenated blood can deliver around 5 ml of O 2 to the tissues under normal physiological conditions.