5C-Regulation of Respiration Flashcards
What two parts of the brainstem control breathing?
Pons and Medulla
What is the group of breathing neurons in the medulla?
medullary respiratory center…CRAZY name, I know
What are the two groups of neurons in the pons?
Ap-neu-stic Center and Pneumo-taxic Center
What is primarily responsible for INSPIRATION and generates the basic RHYTHM for breathing? (What part of the brainstem are we talking here)
DORSAL respiratory group (DRG)..(medulla)
What is the “SA node of breathing”?
DRG (dorsal respiratory group)
CN __ inputs information from peripheral chemoreceptors and mechanoreceptors (e.g., lung stretch receptors, irritant receptors, J receptors and joint & muscle receptors)..
X Vagus!
CN ___ inputs information from peripheral chemoreceptors.
IX Glossopharyngeal
Output from the DRG travels via the _______ nerve to the diaphragm & external intercostals.
phrenic nerve
What is is primarily responsible for expiration?
the VENTRAL respiratory group (VRG)
What is not active during normal, quiet breathing, when expiration is passive?
the VRG
What is activated (e.g., during exercise) when expiration becomes an active process?
The VRG
Which group sends signals to INSPIRATORY MUSCLES?
DRG
Which group sends signals the the EXPIRATORY MUSCLES?
VRG
What was the analogy for the DRG? How long is it active? inactive?
A light switch!…Active for 2 seconds, inactive for 3 seconds. (60sec/5sec=ABOUT 12 breaths/minute!)
What is located in the upper pons and nhibits inspiration and limits the burst of action potentials in the phrenic nerve?
Pneumotaxic Center
What limits the size of the TV?
Pneumotaxic Center
Commands from the _________ can temporarily override the brainstem centers. For example, a person can voluntarily hyperventilate…
cerebral cortex
What does HYPERventilation do to arterial pH? Hypo?
hyperventilation=decrease in CO2=increase in pH (basic)….Hypo=increase in CO2=decrease in pH
What can prolong duration of breath holding?
Prior hyperventilation!
Where are the central chemoreceptors located?
ventrolateral medulla
Where are the peripheral chemoreceptors?
Aortic Arch and Carotid arteries! (same as baroreceptors!!)
What type of fluid do the central chemoreceptors monitor?
The CSF! They only measure Bohr’s effects! pH and CO2
What is the O2 threshold for the peripheral chemoreceptors ?
60mmHg O2
WHICH CHEMICAL has the LARGEST INFLUENCE on respiration (most closely controlled)? What is the threshold for this chemical?
CO2!…+/-3…43=too HIGH=breathe faster!