respiratory 4 Flashcards
ventilation has 4 potential sites of control:
these control the ___ and ___ of ventilation
CNS respiratory control center
peripheral chemoreceptors
central chemoreceptors
mechanical (stretch) receptors in lung
rate & depth
CNS respiratory control center:
ventilation is a vital reflex, so its controlled by ___ and ___
there are diff groups of neurons that contain all the neurons that control rate & depth of breathing:
medulla oblongata & pons
ventral respiratory root, VRG, dorsal respiratory root, DRG
name the 3 types of neurons in the CNS respiratory control center
1- pacemaker neurons: depolarize and fire spontaneously at their own natural rhythm
2- inspiratory neurons: send signals to the respiratory muscles (diaphragm & intercostal muscles), they initiate inhalation
3- expiratory neurons: they shut off the action of the inspiratory neurons and allow the lungs to passively exhale
CNS respiratory control center:
pacemaker neurons make up a central pattern generator, there are a network of pacemaker neurons located in the ___, they set the rhythm for the beginning of the ___ cycle and once they fire, send signals to the ___
preBotzinger complex
inhalation
inspiratory neurons
CNS respiratory control center:
there are 2 groups of inspiratory neurons, one in the ___ and other in the ___, the lungs fill and then…
Botzinger complex
rostal position
expiratory neurons stop the firing
CNS respiratory control center:
normal respiratory rhythm is altered by a number of factors, ___, other neuronal signals can override the normal rhythm to change it…
speech
DRG has both inspiratory & expiratory neurons, believed to function in overriding normal neural signals during transition from rest to exercise (responsible for overinflating lungs & actively exhaling for exercise)
VRG has diff neurons
- pons adds another layer to ventilation
CNS respiratory control center:
inspiratory neurons stat firing ___…
slowly, their frequency and intensity builds & builds –> then expiratory neurons turn on and inspiratory turns off immediately
CNS respiratory control center:
group of neurons in the pons called ____, there are 2 groups, they each exert a more fine control over the ___ and ___
pontine respiratory neurons
inspiratory & expiratory neurons (and help set the max lung volume)
name the 2 centers in the pontine respiratory center
1- pneumotaxic center: sends impulses to DRG to switch off inspiratory neurons, limiting duration of inspiration (turns them off)
2- apneustic center: does opposite, prevents inspiratory inhibition during period of exercise, allows for increased respiratory drive, allows overinflation of lungs
- allows for recruitment of DRG to function more actively during exercise
the pontine respiratory center is also the receiver for ___….it also receives ___ from the ___, which alters…
sensory info that comes from multiple sources, integrates the input
emotional signals from hypothalamus which alters breathing rate depending on emotional state
chemoreceptors (both central & peripheral) monitor ___, ___, and ___ of your blood
PO2, CO2, and pH
name the 2 locations that peripheral chemoreceptor centers are
1- aortic arch in aortic bodies
2- carotid bodies
peripheral chemoreceptors:
the ones in aortic arches monitor the ___ of your blood, in normal conditions, they are ___…
PO2, silent
only become active in extreme cases, when arterial PO2 levels drop to 60mmHg or below
peripheral chemoreceptors:
the ones in carotid bodies, in the carotid sinus, the same place as ___, they are sensitive primarily to ____
baroreceptors
pH, hydrogen ions
peripheral chemoreceptors:
the ones in carotid bodies monitor minute to minute changes in ___ and adjust ventilation maintain constant ___, they are __ active
arterial pH
pH
always active