Control of breathing Flashcards
What is spontaneous respiration produced by
rhythmic discharge of motor neurons that innervate the respiratory muscles
chemical control
changes in metabolic demand of body activate peripheral chemorecetpros which send signals to respiratory center via nerves IX and X,
Where is the automatic system located
pons and medulla
what does the automatic system do
sends impulses to respiratory motor neurons via the white matter of the spinal cord
Where is the voluntary control system
cerebal cortex
what does the voluntary control system do
sends impulses to respiratory motor neurons located in spinal cord via cortico-spinal tracts
What is the major controller of respiration
PCO2
What is different about peripheral and central affects of CO2
stimulation by way of peripheral chemoreceptors occurs 5 times as rapidly as central stimulation
What affect does decreased pH have
stimulates chemorecetpros
does changes in arterial H+ act directly on central chemorecptos
NOPE
low arterial PO2 via the peripheral chemorecptor system incraeses alveolar ventilation _________
independently of PCO2
what is a chemosensitive area
highly sensitive to changes in either blood PCO2 or hydrogen ion conc.
Function of peripheral chemorecetpros
important for detecting changes in blood O2
respond to a lesser extend to changes in CO2 and H+
examples of peripheral chemorecetpors
carotid body
aortic body
What is the chemosesntive area high senstive to
change in PCO2 or H+
What is the sensory integratino site
nucleus of tractus solitary
What is the pre-botzinger complex
located on either side of medulla between nucleus ambiguus and lateral reticular nucleus
contains synaptically coupled neurons
produces rhythmic discharges
What is the dorsal respiratory group
located in dorsal portion of medulla
sends out repetitive burst of inspiratory neuronal AP
main role in controlling inspiration
What is the pneumotaxic center
located dorsally in nucleus parabrachialis of upper pons
transmits signals to inspiratory area
control the switch off point of inspiratory ramp
controls rate and depth of breathing
What is the ventral respiratory group
located in ventro-lateral part of medulla
totally inactive during normal quiet respiration
What happens when respiratory drive for increased ventilation becomes greater than normal
signals spill over to the VRG
where are Irrtiant receptors located
epithelium trachea, bronchi, bronchioles
What do irrtiant receptors cause
coughing, sneezing, bronchial constriction in asthma and emphysema
What are J receptors
sensory nerve ending in alveolar walls in juxtaposition to pulmonary capillaries
