Regulation of Respiration Flashcards
what 3 sensors regulate respiration?
stretch sensors
chemical sensors
irritant receptors
where are stretch sensors located?
bronchi walls
what is the function of stretch sensors?
inhibits inspiration by Hering-Breuer reflex
what is the mechanism of stretch sensors?
- phrenic nerve stimulates diaphragm to contract
- at max inhalation, stretch receptor via vagus inhibits dorsal respiratory group
- inhibits phrenic nerve which inhibits inspiration
what are the 2 types of chemical sensors?
central & peripheral
where are central chemical sensors located?
in respiratory center
what do central chemical sensors respond to?
increased CO2
what is the function of central chemical sensors?
increase ventilation by increasing both inspiration & expiration
where are peripheral chemical sensors located?
in the carotid bodies
what do peripheral chemical sensors respond to?
- decreased O2
- decreased pH (can be increased CO2 due to carbonic acid in RBC)
what is the function of peripheral chemical sensors?
increase ventilation
what do irritant receptors respond to?
inhaled irritants (smoke, perfume, etc)
what is the function of irritant receptors?
cause bronchoconstriction & increased ventilation rate with short, rapid breaths
which type of chemical receptor has the greatest impact on ventilation?
central
what is the function of the dorsal respiratory group?
controls quiet breathing and inspiration via the inspiratory ramp
what is the function of the ventral respiratory group?
extra respiratory drive: forced inspiration & expiration
what is the function of the pneumotaxic center?
limits inspiration, increases rate of breathing
what is the most important pathway for the respiratory response to systemic arterial CO2 (PCO2)?
H+ activation of the chemosensitive area of the medulla
what limits the duration of inspiration and increases respiratory rate?
pneumotaxic center
where are the respiratory neurons that become active during increased respiratory drive located?
ventral respiratory group
where are the afferent endings for the Hering-Breuer reflex (mechanoreceptors) located?
bronchi & bronchioles
when breathing in and out of a bag, what is responsible for the increase in ventilation?
increased alveolar PCO2
