Stimulation Of Breathing

Question 1

Where in the brain do the neurons which control breathing exist?

Answer 1

Medulla oblongata

Question 2

The neurons of the dorsal respiratory group of the medulla oblongata fire during expiration. T/F?

Answer 2

False they fire during inspiration

Question 3

Which muscle is the primary respiratory muscle and which nerve is it innervated by?

Answer 3

Diaphragm

Phrenic nerve

Question 4

Where in the ventral respiratory group of the medulla oblongata is the respiratory rhythm generator?

Answer 4

The pre-Bötzinger complex

Question 5

In addition to containing the respiratory rhythm generator, the ventral respiratory group of the medulla oblongata also contains neurons which fire during which part of breathing?

Answer 5

Expiratiom

Question 6

What is the name of the area of the pons which helps to smooth the transition between inspiration and expiration?

Answer 6

Pneumotaxic centre

Question 7

Other than the pneumotaxic centre, what is the other region of the pons which inputs imto the medullary cardiovascular centre to provide fine tune control over breathing?

Answer 7

Apneustic centre

Question 8

The respiratory nerves of the medulla and pons also receive synaptic inout from higher brain centres. Why is this so?

Answer 8

So that the pattern of breathing can be controlled voluntarily in situations such as when speaking, diving or even with emotions and pain

Question 9

Describe the Hering bruer reflex

Answer 9

Action potential in afferent fibres from stretch receptors in the lung travel to the nucleus tractus solitarius of the brain and inhibit the activity of the medullary inspiration neurons to terminate inspiration when there are large tidal volumes

Question 10

The medullary cardiovascular centre receive input from peripheral chemoreceptors. Where do these reside?

Answer 10

At the bifurcation of each of the common carotid arteries and in the aortic arch

Question 11

Which nerves transmit information from the peripheral chemoreceptors to the nucleus tractus solitarius to provide inout to the medullary cardiovascular centre?

Answer 11

Vagus and glossopharyngeal

Question 12

What factors are peripheral chemoreceptors stimulated by?

Answer 12

Decrease in partial pressure of oxygen
Increased in partial pressure of carbon dioxide
Increase in hydrogen ion concentration

Question 13

Where are central chemoreceptors located?

Answer 13

In the medulla

Question 14

What are the central chemoreceptors stimulated by?

Answer 14

Increased in hydrogen ion concentration

Increased partial pressure of carbon dioxide

Question 15

Progressive reductions in inspired oxygen have very little effect on the firing of inspiratory neurons until a partial pressure of approximately…?

Answer 15

60mmHg

Question 16

Very small changes in partial pressure fo carbon dioxide can have large effects on ventilation. T/F?

Answer 16

True

Question 17

What can cause an increase in partial pressure of carbon dioxide in the blood?

Answer 17

Increased carbon dioxide in inspired air

Pulmonary disease where the body retains carbon dioxide