breathing Flashcards
what are the 3 basic elements of the respiratory control system
sensors, effectors and central controller
what are the 3 elements of the centeral controller
pons, medulla and other parts
effectors example
respiratory muscles
examples of sensors
chemo, lung and mechano receptors
where are the central chemoreceptors located
ventral surface of medulla
or
retrotrapezoid nucleus
what does not cross the blood brain barrier
h+
what diffuses through into the cerebral spinal fluid
co2
co2 binds to what to form carbonic acid
h20
carbonic acid dissociates into what 2 things
h+ and bicarbonate
changes in cerebral spinal fluid activate what
central chemoreceptors
where is the respiratory rhythm is generated
medulla
what is the primary muscle of inspiration
diaphragm
what is the primary regulated variable
partial pressure of co2 - Paco2
which part of the respiratory control system is voluntary
cortical
which part of the respiratory control system is automatic
brainstem
breathing comes under what type of control
cortical / voluntary control and automatic
3 examples of voluntary behavior’s
speech, singing, sniffing, coughing, breath holding
deep seas divers can lower co2 partial pressure via what
hyperventilation prior to breath-holding
hyperventilation can what
half paco2 resulting in alkalosis
what is alkalosis
an increase of alkalie in the blood due to an increase of bases
the urge to breath during a breath hold occurs at what paaco2
50mmHg
the cortex can override the what process
automatic
phrenic motor nuerons receive input from the
primary motor cortex and from the brainstem
direct inputs from the cortex allow for what control of breathing
voluntary
direct inputs from the brainstem allow what control
automatic
a relay from the cortex to brainstem exists via corticobulbar tracts and allows
the cortex to override automatic breathing - speech example
what are the 4 inspiratory muscles
sterno, scalenes, diaphragm and external intercostals
what are the 5 muscles for expiration
internal intercostals, externals and internals obliques,
rectus and transverse abdom,
What is the pontine respiratory group - PRG
a group of neurons in the pons that is involved with regulation if breathing
PRG contains Kolliker - fuse nucleus and parabrachial nucleus - these neurons do what
inhibit inspiration and prolong expiration
what is the PRG responsible for
the hering breur lung inflation reflex
what is the hering lung inflation reflex
aka inflation reflex
triggered to prevent over inflation of lungs - using stretch receptors
where is the dorsal respiratory group
caudal NTS -
what is respiratory neuroplasticity
a persistent change in the neural control system based on experience
why is neuroplasticity important
the change in neural control behaviors is essential to ensure pzco2 homeostasis in the face of recurrent or enduring perturbations - disease or injury
paco2 regulation
adaptive control
the paco2 control is long lasting modifications to the control system - t or f
t
t or f - paco2 adaptive control can occur at multiple levels of respiratory control
t
what feedback system does paco2 use
negative closed loop - chemofeedback
the respiratory control system is not a fixed system t or f
t
equation for neural control system is what
paco2 = gas constant, temperature and vco2 / Va
ventral respiratory group
split into what 2 things
rostral and caudal aspects
rostral - inspiratory - diaphragm and ex intercostals
caudal - expiratory - abdominal and in. intercostals
peripheral chemoreceptors- po2 sensors
has 6 steps
whats the first 2
low pao2 is detected by receptor on glomus cells
k+ channels close
low pao2 is detected by receptor on glomus cells
k+ channels close
peripheral chemoreceptors- po2 sensors
has 6 steps
whats the second 2
cells depolarized opening ca 2 + channels
ca2 enters cell causing atp release
peripheral chemoreceptors- po2 sensors
has 6 steps
whats the third 2
afferent neurons is activated
activated respiratory control centre increase breathing
