Control of respiration

Question 1

What type of breathing is sub-conscious and occurs at rest?

Answer 1

Quiet breathing

Question 2

What is deep breathing?

Answer 2

Sub-conscious or deliberate and increases amplitude of ventilatory movements

Question 3

What is forced breathing?

Answer 3

Deliberate, increases amplitude of ventilatory movements to limit of thoracic volume change

Question 4

What are the short term challenges with the respiratory system?

Answer 4

Maintain oxygen supply and ensure CO2 removal from metabolising tissues

Question 5

What are the long term challenges with the respiratory system?

Answer 5

Avoid or repay oxygen debts and ensure CO2 removal from blood

Question 6

What is the short and long term challenge with the respiratory system?

Answer 6

Maintain blood pH

Question 7

What changes are made to allow different gas supplies?

Answer 7

Frequency of ventilation
Depth of ventilation
Airway resistance
Amount of gas carried in blood
Rate of blood circulation
Passage of blood through tissues

Question 8

How does the brain affect the respiratory system?

Answer 8

Control sub-conscious and conscious ventilation

Question 9

Where is ventilation exerted?

Answer 9

Through nerves to diaphragm and intercostal muscles

Question 10

What are the regulating factors of ventilation?

Answer 10

Blood PCO2, PO2 and H+

Question 11

Where are the pons and medulla located?

Answer 11

Brainstem

Question 12

Where do the pons and medulla receive information from?

Answer 12

Chemoreceptors, stretch receptors and cerebral cortex

Question 13

Where does the pons send signals?

Answer 13

To the medulla

Question 14

Where do signals go from the medulla?

Answer 14

Rhythmically to the spinal cord through inspiratory neurons

Question 15

Where do signals go from the spinal cord?

Answer 15

To the diaphragm through cervical nerve 4

Question 16

What is cervical nerve 4?

Answer 16

Phrenic nerve

Question 17

What are the 4 sections of the brainstem?

Answer 17

Above pons
Mid-pons
Between pons and medulla
Below medulla

Question 18

What occurs in the above pons?

Answer 18

Involuntary respiration with lower rhythmic frequency

Question 19

What occurs in the mid-pons?

Answer 19

Lower frequency, deeper inspiration

Question 20

What occurs between the pons and medulla?

Answer 20

Gasping or irregular inspiration

Question 21

What occurs below the medulla?

Answer 21

No voluntary respiration

Question 22

Role of cortex

Answer 22

Controls voluntary respiration

Question 23

Role of pneumotaxic centre (PC)

Answer 23

Terminates and limits inspiration

Question 24

What prevents inspiratory neurons from being turned off?

Answer 24

Apneustic centre (AC)

Question 25

What is in the medulla?

Answer 25

Inspiratory and expiratory control centres

Question 26

Role of ventral respiratory group/column

Answer 26

Regulates amplitude and frequency of ventilation

Question 27

Role of dorsal respiratory group (DRG)

Answer 27

Transfers inspiratory signals to diaphragm

Question 28

What are the central chemoreceptors?

Answer 28

Medullary respiratory centres

Question 29

What are the peripheral chemoreceptors?

Answer 29

Aortic and carotid bodies

Question 30

Where are carotid bodies located?

Answer 30

On each side near carotid artery

Question 31

Role of carotid bodies

Answer 31

Monitor H+ and O2

Question 32

Where are aortic bodies located?

Answer 32

Near the aortic arch

Question 33

Role of aortic bodies

Answer 33

Monitor O2

Question 34

Where do aortic and carotid bodies’ afferent nerves transfer signals?

Answer 34

Medulla and pons through vagus and glossopharyngeal nerves

Question 35

What happens when arterial PO2 is low?

Answer 35

Peripheral chemoreceptors detect the change and increase ventilation

Question 36

How are PCO2 levels detected?

Answer 36

Central chemoreceptors monitoring pH in the ECF

Question 37

What happens when inspired CO2 increases?

Answer 37

Rate and depth of ventilation increases

Question 38

When is ventilation maximum?

Answer 38

At 6.6% CO2

Question 39

What happens if CO2 becomes higher than 6.6%?

Answer 39

Acidosis occurs because CO2 can’t be removed by hyperventilation