Control of Lung

Question 1

What is the dorsal respiratory group

Answer 1

Inspiratory centre

Controller of inspiration

Set rate

Question 2

What is the ventral respiratory group

Answer 2

Expiratory centre

Inactive during quiet breathing

Inhibit apneustic centre

Question 3

What is apneustic centre

Answer 3

Stimualte activity in DRG

Inhibited by pulmonary afferents

Question 4

What is pneumotaxic centre

Answer 4

Inspiratory off switch

Regulates depth and frenquency

Question 5

What is DIVE

Answer 5

Dorsal inspiration Ventral expiration

Question 6

How does C02 get pass the blood brain barrier

Answer 6

Co2 is highly lipid soluble can pass through the blood brain barrier

Question 7

What are irritant receptors affect ventilations

Answer 7

Afferent receptors embedded within and beneath airway epithelium

Leads to cough: forecful expiration against closed glottis with sudden glottal opening leading to high velocity expulsion

Question 8

What are stretch receptors

Answer 8

Excessive inflation of lungs which activates pulmonary stretch receptors

Afferent signals inhibit DRG and apneustic centre and stimulate pneumotaxic VRG

Inspiration inhibited and expiration stimulated

Question 9

What are J receptors in the lung

Answer 9

Sensitive to oedema (swellign fluid and high pressure in pulmonary vessels) and pulmonary capillary engorgement

Increase breathing frequency

Question 10

How does volitional apnoea happen

Answer 10

Increase in the starting level of oxygen

CO2 threshold for breathing is closer to o2 treshold for blackout

Question 11

Why does the acidity of blood need to be regulated

Answer 11

Alter the 3D structure of proteins

Question 12

Why did the dog not die after beign injected with acid

Answer 12

Has an enormous buffering capacity and can react almost immediately to imbalances

Question 13

What is alkalaemia

Answer 13

High than normal pH of blood

Question 14

What is acidaemia

Answer 14

Lower than normal pH of blood

Question 15

What is alkalosis

Answer 15

Circumstances that will decrease protons and increase pH

Question 16

What is acidosis

Answer 16

Circumstances that will increase portons and decrease pH

Question 17

Why do you use ventilation to change the pH

Answer 17

Stimulate a RAPID compensatory response to change CO2 elimination and alter pH

Kidney stimulate a slow compensatory response

Question 18

Why is having chemoreceptors in the aortic arch important

Answer 18

This is where most of the blood going to the brain comes from

Question 19

What are the emotional changes to ventilation

Answer 19

Special senses are switched on which triggers an emotional response

Limbic system is involved which is close to brainstem

Question 20

What happens during breathing during exercise

Answer 20

Efferents from primary motor cortex to skeletal musculature partially innervate medulla

Afferents from muscle and golgi tendon innervate medulla on the way to brain

Question 21

What happens when skin gets cold on breathing

Answer 21

Immersion in cold water <10C induces hyperventilation/inspiratory gasp

due to superficial nerve endings in the skin