Question

The pontine respiratory group is responsible for all of the following functions, except:

a) causing apneustic breathing if it is damaged.
b) regulating and modifying the activity of the medullary neurons.
c) smoothing out the transition from inspiration to expiration.
d) stimulating the contraction of the diaphragm.

Answer 1

The pontine respiratory group does not stimulate the contraction of the diaphragm; that function is managed by the medullary dorsal respiratory group and ventral respiratory group.

Step-by-step explanation:

The function that the pontine respiratory group is not responsible for is d) stimulating the contraction of the diaphragm. The pontine respiratory group includes the apneustic and pneumotaxic centers, which are involved in regulating the depth of inspiration and the rate of breathing, respectively. If damaged, the apneustic center can cause apneustic breathing, which is characterized by pathologically prolonged inspiratory gasps followed by insufficient release into expiration. The pneumotaxic center modified the activity of neurons in the medullary dorsal respiratory group (DRG), smoothing out the transition from inspiration to expiration but it does not directly stimulate diaphragmatic contraction; that function is primarily attributed to the DRG and ventral respiratory group (VRG) in the medulla oblongata.