Normal Physiology - Control of breathing

Question 1

What does the metabolic hyperbola describe?

Answer 1

Alveolar gas tensions for different levels of ventilation

Question 2

Respiratory control system ensures…

Answer 2

stability of arterial blood gas partial pressures for O2 and CO2

Question 3

How is respiratory control system an automatic system?

Answer 3

Because there is a respiratory pacemaker…

Question 4

What is the Prebotzinger complex?

Answer 4

respiratory pacemaker

Question 5

What is the nucleus of the solitary tract?

Question 6

What is the Botzinger complex?

Question 7

7th cranial nerve - parafacial respiratory ???

Answer 7

Where Co2 is predominantly sensed

Question 8

What is KS

Answer 8

Kalakarfusa

Question 9

Activity of the central controller is mediated by inputs from…

Answer 9

• chemoreceptors
• lung parenchymal and airway afferents
• chest wall
• upper airway

Question 10

How are the carotid bodies involved in O2 sensitivity?

Question 11

What are the cell types within the carotid bodies

Answer 11

capillary network, glomus cells, subtentacular cells, fibres of carotid sinus nerve

Question 12

What do the fibres of carotid sinus nerves do?

Question 13

Normally, in a carotid body there is a…

Answer 13

ouitward potassium current out of the glomus cells.

Question 14

What happens to the otassium channels when O drops?

Answer 14

Potassium channels are blocked ….. action potential is generated…

Question 15

What are gasotransmitters? Name .

Question 16

Hemoxygenase II is consituitively expressed to produce…

Answer 16

carbon monoxide

Question 17

When carbon monoxide is present in ….

Question 18

To keep potassium channles open you need low levels of H2S

Question 19

Describe the ventilatory response to hypoxia

Question 20

Water and carbone dioxide are in equilibrium with… (Henderson Hasselbalch Equation) in the blood

Question 21

Where is the co2 sensor

Answer 21

On the vcentral side of the medulla

Question 22

Can the hydrogen ion cross the blood brain barrier? How is this solved?

Answer 22

No - equilibrium equation (?)

Question 23

Where does CO2 sensing occur?

Answer 23

In retrotrapezoid nucleus

Question 24

Describe hypoxia

Answer 24

Rapid, shallow (i.e. relatively greater increase in frequency than tidal volume)
Minimizes O2 cost of breathing (curvilinear pressure-volume relationship of lung inflation)

Question 25

Describe hypercapnia