Which of the following statements about the transport of respiratory gases by the blood is false? the amount of o2 that can be dissolved directly in plasma is sufficient to support the resting metabolism. by binding o2, hemoglobin maintain the o2 concentration gradient. internal ventilation of the gas exchange surfaces is dependent on blood flow. each hemoglobin molecule can carry a maximum of four o2 molecules. molecules of o2 are associated with the heme groups of hemoglobin.