24

Question 1

where’s the respiratory control cnetre

Answer 1

pon and medulla

Question 2

four inputs to respiratory centre

Answer 2

1. voluntary control via cerebum
2. central chemoreceptor
3. peripheral chemoreceptr so carotid and aortic
4. mechanoreceptor in lung
5. muscle proprioreceptos

Question 3

what does the respiratory control centre innervate

Answer 3

spinal motor neurones

Question 4

what do spinal motor neurones innervate

Answer 4

respiratory muscles

Question 5

where does CSF get formed

Answer 5

choroid plexus

Question 6

how is CO2 increase sensed

Answer 6

CO2 diffuses to CSF where it becomes carbonic acid bc interacts w water. csf has CA so carbonic acid becomes H plus and bicarbonate. Hplus is sensed by central chemoreceptors in the ventral surface of medulla

Question 7

where are central chemoreceptors found

Answer 7

ventral surface of medulla

Question 8

if csf is acidic would you have more or less ventilation

Answer 8

more because you want to expel CO2

Question 9

what do chemoreceptors send signals to

Answer 9

respiratory neurones

Question 10

normal pH of CSF

Answer 10

7.32

Question 11

why does CSF have much lower buffering capacity than blood

Answer 11

bc it has no proteins.

Question 12

what types of receptors exist in the lungs

Answer 12

1. stretch receptors
2. irritants
3. J receptors

Question 13

where are stretch rectors found

Answer 13

bronchioles and small bronchi

Question 14

function of stretch receptors

Answer 14

inhibit inspiration when lungs are fully inflated. send AP to vagus nerve to respiratory centre in pons and medulla to inhibit phrenic innervation of diaphragm

Question 15

whats the Hering Breuer inflation reflex

Answer 15

its the mechanism by which when your lungs are fully inflated they won’t inflate more because the stretch receptors in the lungs send a message to the vagus nerve to prevent phrenic innervation of diaphragm.

Question 16

where are irritant receptors found

Answer 16

trachea and primary bronchi

Question 17

function of irritant receptors

Answer 17

detect presence of foreign object, activate cough reflexes

Question 18

what type of receptors are J receptors

Answer 18

chemoreceptors.

Question 19

function of j receptors

Answer 19

respond to Edema Emboli…
detect fluid in alveoli
send signal via vagus to increase ventilation and respiration

Question 20

whats the shape of the curve of ventilation depending on partial pressure of CO2

Answer 20

linear

Question 21

what increases sensitivity to CO2

Answer 21

hypoxia

Question 22

at what partial pressure of O2 will hypoxia be taken into consideration by respiratory centres

Answer 22

60 mmHg sinon it reamin unchanged

Question 23

what hypercapnia

Answer 23

increase in CO2 partial pressure

Question 24

where are sensors for hypoxia

Answer 24

in peripheral chemoreceptors
carotid body on top of bifurcation
and below and above aortic arch

Question 25

what structure contains the most heavily vascularised tissue in the human body

Answer 25

carotid body

Question 26

what cells make up the carotid body

Answer 26

type I glomus cells (chief cells) like chromatin cells, produce neurotransmitter that stimulate glossopharyngeal nerves that project to respiratory centres. 
type II (sustentacular cells): normal CT supportive like glia

Question 27

how does SNS affect carotid body

Answer 27

increases sensitivity to hypoxia

Question 28

how do type 1 glomus cells detect hypoxia

Answer 28

hypoxia leads to closure of K channels.so Na and Ca channels open causing the realise of NT like acetylcholine which act on receptors on afferent nerve fibres near glomus and cause AP to go to respiratory centres

Question 29

what receptor is the main contributor to breathing urge

Answer 29

central chemoreceptor

Question 30

pulmonary receptors all input to

Answer 30

NST which projects to dorsal respiratory area. (medullary reticular formation)

Question 31

what neurones become active during forced expiration

Answer 31

neurones in the ventral respiratory area which go to the reticulospinal tract

Question 32

which side of the respiratory area is involved with inspiration?

Answer 32

dorsal

Question 33

which side of the respiratory area is involved with expiration?

Answer 33

ventral

Question 34

what regulates medullary respiratory region

Answer 34

the apneustic centre

pneumotaxic centre

Question 35

what does the apneustic centre cause

Answer 35

prolonged inspiration

Question 36

voluntary breath holding is achieved by what

Answer 36

apneustic centre

Question 37

what does the pneumotaxic centre cause

Answer 37

inhibits apneustic centres
regulates breathing for singing
but cannot completely override medullar centre so can’t hold breath for too long.