08.14 - Control of Breathing (Leffler) - Questions

Question 1

Which group of neurons sends output to motor neurons

Answer 1

Ventral Respiratory Group

Question 2

2 areas that modulate the Ventral Respiratory Group

Answer 2

Dorsal Respiratory Group (Receives peripheral inputs), PreBotzinger Complex

Question 3

Where is the central respiratory control center located

Answer 3

Medulla

Question 4

Role of the Apneustic Center

Answer 4

Inspiration prolonging

Question 5

Role of Pneumotaxic Center

Answer 5

Respiratory rate regulation - Inhibits medullary inspiratory neurons

Question 6

What is the Hering Breuer Reflex

Answer 6

Inflation of the lungs inhibits inspiration - Vagal fibers from pulmonary stretch receptors - Above 1 L tidal volume

Question 7

Reflex that senses increase of tidal volume above 1 L

Answer 7

Hering Breuer Reflex

Question 8

How does blood pressure affect ventilation

Answer 8

Decrease in blood pressure (baroreceptors) increases ventilation

Question 9

Role of the Gamma-efferent fibers

Answer 9

Detects and responds to changes in lung compliance or airway resistance

Question 10

Detects and responds to changes in lung compliance or airway resistance

Answer 10

Gamma-efferent fibers

Question 11

Coughing due to irritants is carried along which pathway

Answer 11

Vagus

Question 12

Role of J-Receptors

Answer 12

Increases in pulmonary blood volume causes rapid shallow breathing

Question 13

Effect of Increases in pulmonary blood volume

Answer 13

Rapid shallow breathing via J-Receptors

Question 14

Textbook PO2

Answer 14

95 mmHg

Question 15

Textbook PCO2

Answer 15

40 mmHg

Question 16

Alveolar ventilation is regulated in response to ___, ___, and ___

Answer 16

PCO2, pH, and PO2

Question 17

Changes in what affect predominant minute-to-minute changes in Alveolar Ventilation

Answer 17

PaCO2

Question 18

What determines PaCO2?

Answer 18

VCO2 / VA

Question 19

How does bicarb cross BBB?

Answer 19

Bicarb/Cl exchanger (electroneutral)

Question 20

How does Incr. PaCO2 affect HCO3- in medulla

Answer 20

PaCO2 up -> pHmedulla down -> HCO3- enters medullary tissue and CSF –> pHmedulla up –> Decr respiratory drive

Question 21

Primary peripheral chemosenstive cells

Answer 21

Carotid Bodies (afferent to ventral respiratory group)

Question 22

How do carotid bodies sense PO2?

Answer 22

O2-sensitive K+ Channels

Question 23

How do O2-sensitive K Channels signal O2 changes

Answer 23

Decr O2 -> Depolarizes -> Excitatory NT’s to Glossopharyngeal

Question 24

What do O2-sensitive K channels specifically sense?

Answer 24

Arterial PO2, not O2 content (doesn’t take into account Hb content)

Question 25

Response speed of carotid body O2-sensitive K channels

Answer 25

Fast

Question 26

Differences in specificities of Central Chemosensitive vs Peripheral Chemosensitive centers

Answer 26

Central do not care about O2; Peripheral care about O2, pH, and PaCO2

Question 27

What happens when PaCO2 increases to 50 from 40 mmHg?

Answer 27

Big increase in ventilation

Question 28

How does decr PaO2 affect bicarb in brain

Answer 28

Decr PaO2 -> Incr VA -> Decr PaCO2 -> Incr pHCC -> Bicarb out -> Decr pHCC => Incr VA for PaCO2

Question 29

How does brain increase PAO2 at higher altitude?

Answer 29

Set lower level of PaCO2 via higher level of ventilation

Question 30

How does plasma HCO3- change during progressive incr in VA

Answer 30

Decreases as compensation for respiratory alkalosis

Question 31

Why is it bad to give 100% O2 to patient with chronic lung disease

Answer 31

Their respiratory centers will have reset to compensate and giving high O2 will cause them to shut down

Question 32

Bicarb moves toward ___ at BBB

Answer 32

Lower pH

Question 33

Breathing in Diabetes

Answer 33

Decr insulin -> Incr fat breakdown -> Incr FA’s -> Deep rapid breathing

Question 34

Kussmaul Respiration

Answer 34

Decr insulin -> Incr fat breakdown -> Incr FA’s -> Deep rapid breathing