Control of respiration Flashcards
What are chemoreceptors stimulated by?
Changes in the chemical composition of their immediate environment
What do chemoreceptors do?
Help to control breathing rate to ensure adequate removal and entry of gases
Where are peripheral chemoreceptors located?
Carotid body and aortic body
What do the peripheral chemoreceptors detect?
Large changes in the partial pressure of oxygen as the arterial blood leaves the heart
What happens when oxygen levels are low?
Afferent impulses travel via the glossopharyngeal and vagus nerves to the medulla oblongata and pons in the brainstem
What responses aim to restore p02
increase in resp rate and tidal volume, blood flow directed to the kidneys and brain, cardiac output is increased.
Where are central chemoreceptors located?
In the medulla oblongata in the brainste,
What do the central chemoreceptors detect?
changes in arterial partial pressure of pC02
What happens when changes in pC02 are detected?
Receptors send impulses to the respiratory centres in the brainstem which initiate changes to restore pCO2
What responses are induced by an increase in pCO2?
Increased ventilation
What responses are induced by an decrease in pCO2?
Decreased ventilation
How do central chemoreceptors detect changes in arterial pC02
Changes in pH in the CSF, as the pH of the CSF is inversely proportional to the arterial pCO2
What happens to the pH of the CSF when there is a decrease in pC02?
The pH is increased which stimulates the respiratory centers to decrease ventilation
What happens to the pH of the CSF when there is a increase in pC02?
The pH is decreased which stimulates the respiratory centres to increase ventilation
What is hypoxia?
Tissues in the body don’t have enough oxygen
