Regulation of Respiratory System I/II Flashcards Preview

CVRH Exam 3 > Regulation of Respiratory System I/II > Flashcards

Flashcards in Regulation of Respiratory System I/II Deck (25):
1

Where is a cycle of inspiration and expiration automatically generated?

In the CNS central pattern generator (CPG)

2

What drives the CPG?

Chemoreceptors (both central and peripheral) sensing PO2, PCO2 and pH

3

What does the CPG regulate specifically?

Respiratory muscles, most importantly the diaphragm

4

What is eupnea?

Quiet, normal, easy breathing

5

What does negative feedback on the CPG come from?

An increase in alveolar ventilation

6

How is the CPG affected b higher center respiratory motor activity?

They send inputs to the CPG during intense exercise

7

Where is the central pattern generator located?

Ventrolateral medulla oblongata

8

What does the pons do in respiration?

It only modulates respiratory output but is not necessary for respiratory output itself

9

What is the dorsal respiratory group (DRG)?

Has sensory input and contains primarily inspiratory neurons

10

Where are the DRG found?

Nucleus of solitary tract in the medulla

11

What is the ventral respiratory group (VRG)?

Primarily motor and contains both inspiratory and expiratory neurons

12

What is the CPG composed of?

DRG and VRG

13

What center can terminate inspiration?

Pontine apneustic center

14

What modulates the apneustic center and fine tunes respiration?

Pneumotaxic center

15

What do peripheral chemoreceptors respond to?

Primarily sensitive to decreasing PO2 less so to increase in PCO2 and decreased pH

16

What are central chemoreceptors sensitive to?

Increase in arterial PCO2 (H+)

17

What generates the respiratory rhythm?

Pacemaker neurons or synaptic interactions within the CPG

18

What is the chemosensor in the carotids and aortic bodies?

Glomus cell

19

What does acidosis cause in the carotid chemosensors?

Makes it more sensitive to arterial PCO2

20

What occurs when PaCO2 goes from 40 to 45 mmHg?

Ventilation will double

21

How does the central chemoreceptor respond to CO2 and H+?

CO2 can cross BBB but H+ cannot therefore the brain responds to local acidosis

22

What stimulates ventilation more hypoxia or respiratory acidosis?

Respiratory acidosis

23

What do juxtacapillary (J receptors) do?

Sense mechanical or chemical irritants and elicit rapid and shallow breathing, bronchoconstriction and mucous secretion as a defense mechanism

24

What do the slowly-adapting pulmonary stretch mechanoreceptors (PSR) do?

Detect lung volume and inhibit the medullary output to phrenic motor neurons producing Hering-Breuer Reflex

25

What does the Hering-Breuer reflex do?

Stops over-inflation of the lungs