Which of the following statements are true of the peripheral chemoreceptors?
I.They account for only 20% to 30% of the ventilatory response to hypercapnia.
II.Unlike the central chemoreceptors, the carotid bodies are directly exposed to arterial blood.
III.The initial ventilatory response to metabolic acidosis is fairly quick.
IV.They are the most important mechanisms that respond to hypercapnia.

Question

Quizplus · Accepted Answer

The peripheral chemoreceptors account for only 20% to 30% of the ventilatory response to hypercapnia. However, the peripheral chemoreceptors respond to increased arterial [H?] about five times more quickly than the central chemoreceptors. Unlike the central chemoreceptors, the carotid bodies are directly exposed to arterial blood. Thus, the initial ventilatory response to fixed acid accumulation is quick, offsetting the fact that H? ions cross the blood-brain barrier with great difficulty.

Which of the Following Statements Are True of the Peripheral