Which of the following statements about the role of the respiratory system in maintenance of blood ph is not true? select one:
a. increasing the breathing rate rids the body of hydrogen ions because more carbon dioxide is breathed out. b. the respiratory center in the medulla oblongata increases the breathing rate if the hydrogen ion concentration of the blood rises. c. the lungs are able to rid the body of a wide variety of acidic and basic substances, thereby directly adjusting the ph of the blood. d. breathing readjusts the proportion of carbonic acid and bicarbonate ions in the blood. e. when the buffer system of the blood is overwhelmed by an acidic or basic substance, the respiratory center adjusts the breathing rate to compensate.

c. The lungs are able to rid the body of a wide variety of acidic and basic substances, thereby directly adjusting the pH of the blood

Explanation:

Lungs help maintain the blood pH by regulating the partial pressure of CO2 and thereby, the amount of hydrogen and bicarbonate ions in the blood. As CO2 enters the blood, it is converted to carbonic acid (H2CO3) which in turn dissociates into hydrogen ions and bicarbonate ions. As the H+ concentration increases, the blood pH decreases. The increased breathing rate and increased gaseous exchange in the lungs compensate for the change in the blood pH. Removal of CO2 from blood reduces the H+ concentration in the blood and thereby, the blood pH is increased towards the normal range.

it has one origin of replication, but it proceeds in two directions - d)