Chapter 36: Regulation of Respiration

Chapter 36. Regulation of Respiration

The main respiratory control neurons

A. send out regular bursts of impulses to expiratory muscles during quiet respiration.

B. are unaffected by stimulation of pain receptors.

C. are located in the pons.

D. send out regular bursts of impulses to inspiratory muscles during quiet respiration.

E. are unaffected by impulses from the cerebral cortex.

Intravenous lactic acid increases ventilation. The receptors responsible for this effect are located in the

A. medulla oblongata.

B. carotid bodies.

C. lung parenchyma.

D. aortic baroreceptors.

E. trachea and large bronchi.

Spontaneous respiration ceases after

A. transection of the brainstem above the pons.

B. transection of the brainstem at the caudal end of the medulla.

C. bilateral vagotomy.

D. bilateral vagotomy combined with transection of the brainstem at the superior border of the pons.

E. transection of the spinal cord at the level of the first thoracic segment.

The following physiological events that occur in vivo are listed in random order: (1) decreased CSF pH; (2) increased arterial Pco₂; (3) increased CSF Pco₂; (4) stimulation of medullary chemoreceptors; and (5) increased alveolar Pco₂.

What is the usual sequence in which they occur when they affect respiration?

A. 1, 2, 3, 4, 5

B. 4, 1, 3, 2, 5

C. 3, 4, 5, 1, 2

D. 5, 2, 3, 1, 4

E. 5, 3, 2, 4, 1

The following events that occur in the carotid bodies when they are exposed to hypoxia are listed in random order: (1) depolarization of type I glomus cells; (2) excitation of afferent nerve endings; (3) reduced conductance of hypoxia-sensitive K⁺ channels in type I glomus cells; (4) Ca²⁺ entry into type I glomus cells; (5) decreased K⁺ efflux.

What is the usual sequence in which they occur on exposure to hypoxia?