Week 8- Control of Lung Function Flashcards
What are the 4 centres found in the medulla oblongata?
Dorsal respiratory group
Ventral respiratory group
Apneustic center
Pneumotaxic centre
What are the inspiratory and expiratory groups? What acronym can be used to remember them?
DIVE: dorsal inspiratory, ventral expiratory
What is the role of the dorsal respiratory group?
Inspiratory centre, controls inspiration and sets the rate
What is the role of the ventral respiratory group?
Expiratory centre, inactive during quiet breathing
What is the role of the pneumotaxic centre?
Its the inspiratory off switch, regulates depth and frequency
What does the pneumotaxic centre inhibit/stimulate?
Inhibits the dorsal respiratory group
What does the apneustic centre inhibit/stimulate?
Stimulates the dorsal respiratory group
What does the dorsal respiratory group inhibit/stimulate?
Inhibits the ventral respiratory group
What does the ventral respiratory group inhibit/stimulate?
Inhibits the dorsal respiratory group and the apneustic centre
When are the apneustic and pneumotaxic centres active during an action potential when theres quiet breathing?
Apneustic: at the bottom of the sloping line (start of AP)
Pneumotaxic: at the top of the sloping line (end of AP)
What respiratory muscles do motor nerves innervate?
Intercostal muscles
What respiratory muscles do sympathetic nerves innervate?
The spine
What respiratory muscles do parasympathetic nerves innervate?
Of the pulmonary plexus
What common molecule can cross the blood brain barrier and why?
Co2 as its lipid soluble
What does Co2 enter after crossing the blood brain barrier?
CSF
What happens to Co2 after it has crossed the blood brain barrier and is in the CSF?
It combine with water to form carbonic acid, which then dissociates, the H+ formed then enters the medulla and goes to the dorsal respiratory nucleus
Why is it helpful that Co2 can cross the blood brain barrier?
It is an indicator of metabolism, so the vol of H+ that reaches the medulla/dorsal respiratory nuclei can indicate to the brain how much metabolism is occurring in the body
What 3 receptors in the pulmonary system affect ventilation?
Irritant receptors
Stretch receptors
J receptors
Where are irritant receptors found?
In and underneath the epithelial lining of the trachea
Where are stretch receptors found?
In the bronchi, deeper in the airway
Where are J receptors found?
At the alveoli