Question

which of the following is (are) true with regard to breathing? a. the diaphragm and intercostal muscles contract when stimulated by afferent nerves b. inspiration is initiated by action potentials from the drg c. the vagus nerve innervates the diaphragm d. the vrg is located in the pons, in front of the drg e. all of the above

Answer 1

The only true statement with regard to breathing, according to the provided reference material, is option (b) - inspiration is initiated by action potentials from the dorsal respiratory group (DRG).

Step-by-step explanation:

The respiratory system is the network of organs and tissues that help you breathe. It includes your airways, lungs and blood vessels.

The muscles that power your lungs are also part of the respiratory system. These parts work together to move oxygen throughout the body and clean out waste gases like carbon dioxide.

With regard to breathing:

• The diaphragm contracts when stimulated by efferent, not afferent, nerves, so option (a) is incorrect.
• Yes, inspiration is initiated by action potentials from the dorsal respiratory group (DRG), so option (b) is true.
• The phrenic nerve, not the vagus nerve, innervates the diaphragm, making option (c) incorrect.
• The ventral respiratory group (VRG) is located in the medulla oblongata, not in the pons, and is located ventral to the DRG, so option (d) is incorrect.

Therefore, the correct option here is inspired by action potentials from the DRG, as stated in option (b).