respiration control of breathing

Question 1

what is breathing modulated by?

Answer 1

• reflexes
• volatile control
• vocalisation
• emotional events
• physiological challenges

Question 2

what does the brain receive neural signals about breathing from?

Answer 2

• chemoreceptors
• mechanoreceptors

Question 3

what do chemoreceptors feedback to the brain?

Answer 3

blood PO2, PCO2 and pH

Question 4

what do mechanoreceptors feedback to the brain?

Answer 4

mechanical status of the lungs, chest wall and airways

Question 5

where does the brain send neural signals to?

Answer 5

• respiratory muscles
• upper airway muscles
• produce reflexes

Question 6

what do the neural signals to respiratory muscles do?

Answer 6

produce rhythmic breathing movements, e.g., diaphragm and intercostals

Question 7

what do the neural signals to upper airway muscles do?

Answer 7

e.g., laryngeal, pharyngeal and tongue

Question 8

what are the reflexes from brain signals include?

Answer 8

reflexes to keep airways patent, e.g., cough, sneeze, gag

Question 9

where are many important neuronal cell groups involved in breathing regulation found?

Answer 9

the brainstem

Question 10

what is a decrease in O2 called?

Answer 10

hypoxia

Question 11

what is an increase in CO2 called?

Answer 11

hypercapnia

Question 12

what are the two types of chemoreceptors?

Answer 12

peripheral and central

Question 13

where are peripheral chemoreceptors located?

Answer 13

region of aortic arch and carotid sinuses

Question 14

where do chemoreceptors send their information through?

Answer 14

via the glossopharyngeal (from carotid) and vagus (from aortic) nerves to the nucleus in brainstem called NTS

Question 15

what do peripheral chemoreceptors primarily respond to?

Answer 15

decreases in PO2 (hypoxia)

Question 16

what is the sequence of steps during a hypoxic environment?

Answer 16

• Reduction in arterial PO2
• Peripheral chemoreceptors stimulated.
• Neural signals sent from carotid and aortic bodies to NTS in brainstem.
• Ventilation increases to restore PO2 levels.

Question 17

what mmHg triggers progressive hyperventilation?

Answer 17

<60mmHg

Question 18

what do central chemoreceptors primarily respond to?

Answer 18

increased PCO2 (hypercapnia), or decreased pH

Question 19

where are central chemoreceptors located?

Answer 19

clusters of neurones in the brainstem

Question 20

where are central chemoreceptors located?

Answer 20

clusters of neurones in the brainstem

Question 21

what is the sequence of steps during a hypercapnia?

Answer 21

• Increase in arterial PCO2
• Central chemoreceptors (brainstem neurones) stimulated.
• Signals processed and information passed on to neuronal clusters in brainstem involved in generating breathing.
• Ventilation increases to restore PCO2 levels.

Question 22

does a small change in PCO2 have a small or big effect on ventilation?

Answer 22

BIG

Question 22

does a small change in PCO2 have a small or big effect on ventilation?

Answer 22

BIG

Question 22

does a small change in PCO2 have a small or big effect on ventilation?

Answer 22

BIG

Question 23

does a small change in PCO2 have a small or big effect on ventilation?

Answer 23

BIG

Question 24

what are mechanoreceptors?

Answer 24

• sensory receptors that detect changes in pressure, movement and touch
• in respiratory system mechanoreceptors detect movement of lung and chest wall

Question 25

what are the mechanoreceptors in the respiratory system activated by?

Answer 25

the inflation of the lungs

Question 26

what happens after the mechanoreceptors detect lung inflation?

Answer 26

neural signals sent via vagus nerve to Nucleus Tractus Solitarius in brainstem

Question 27

what processes the information from mechanoreceptors and peripheral chemoreceptors?

Answer 27

respiratory neurones

Question 28

what is the stimulus and reflex of mechanoreceptors in the airways on smooth muscle?

Answer 28

Stimulus: Inflation/distension of airways
Reflex: Termination of inspiration

Question 29

what is the stimulus and reflex of mechanoreceptors in the airway epithelium?

Answer 29

Stimulus: Rapid lung inflation or deflation, or oedema
Reflex: Sigh or shortened expiration

Question 30

what do the respiratory neurones do with the information?

Answer 30

generate rhythm of breathing

Question 31

what are the types of respiratory neurones?

Answer 31

inspiratory and expiratory

Question 32

nucleus tractus solitarius

Question 33

what does the phrenic nerve innervate?

Answer 33

the diaphragm

Question 34

what is the output sequence from the brainstem to respiratory muscles?

Answer 34

• Brainstem neurones produce rhythmic output.
• Rhythmic neural signals sent to spinal cord.
• Phrenic nerve exits spinal cord at cervical spinal cord level 3-5.
• Phrenic nerve innervates diaphragm.
• Nerves exiting thoracic spinal cord innervate intercostal muscles.

Question 35

what is another name for the nucleus trachtus solitariius?

Answer 35

dorsal respiratory group

Question 36

where does neural output to muscles come from?

Answer 36

ventral respiratory group

Question 37

pontine respiratory group

Question 38

what types of breathing control comes from the higher centre modulation?

Answer 38

volitional and emotional

Question 39

why is there a large portion of the motor cortex dedicated to the hand?

Answer 39

refined movement