resp system 2 Flashcards
pontine respiratory group
In Pons
sending input to DRG
Helps to accomodate : exercising, speakings
mechanoreceptors
- found in joints and muscles (proprioceptors); respond to changes in body movement (rest-exercise/ quiet breathing - more forceful)
- send input signal to DRG; help recruit VRG
slowly adapting receptors -Hering Breuer reflex
- found in smooth muscle surrounding airways; respond to changes in lung volume
- terminates inspiratory neurons in DRG if large volume breathes
- protective function : preventing over expansion of lungs
rapidly adapting receptors
found in larger airway epithelium; respond to noxious gases, cold air, inhaled particles
- “irritant receptors” triggering airway narrowing, mucus production and coughing
- protective function : limit irritants getting to lungs
Peripheral chemoreceptors
carotid sinus and aortic arch
-respond to changes in arterial blood
stimulated by :
- decreased arterial PO2
- increased metabolic acidosis generating arterial H+
- increased arterial PCO2 generating arterial H+
central chemoreceptors
medulla oblongata (IN CNS)
-respond to changes in brain extracellular or Cerebrospinal fluid
stimulated by:
-increased brain PCO2 generating brain H+
temporarily stop breathing under voluntary control
= Apnea
- increase CO2 to critical level = involuntary breathing starts
- decrease oxygen to critical level = unconsciousness, breathing should resume
voluntary actions
come from cerebral or motor cortex of brain
tidal volume
amount of air inhaled or exhaled in one breath
inspiratory reserve volume (IRV)
amount of air in excess of tidal inspiration that can be inhaled with maximum effort
expiratory reserve volume (ERV)
amount of air in excess of tidal expiration that can be exhaled with maximum effort
residual volume (RV)
amount of air remaining in lungs after maximum expiration
-keeps alveoli inflated between breaths and mixes with fresh air on next inspiration
vital capacity
amount of air that can be exhaled with maximum effort after maximum inspiration
inspiratory capacity
maximum amount of air that can be inhaled after a normal tidal expiration
functional residual capacity (FRC)
amount of air remaining in lungs after a normal tidal expiration
total lung capacity
maximum amount of air lungs can contain
forced vital capacity (FVC)
volume of air expired forcefully after maximum inspiration
forced expiratory volume in 1 sec (FEV1)
volume of air expired forcefully in the 1st scond of FVC
FEV1/ FVC
percentage of total FVC expired in 1st second
obstructive lung disease
hard to exhale all the air in lungs
-low FEV percentage
restrictive lung disease
difficulty fully inspiring air into lungs
-higher FEV percentage or same as in normal
ventilation
combine tidal volume (depth of breathing) and breathing frequency (rate of breathing)