5.5 Flashcards
What muscles are the diaphragm and intercostals
skeletal muscles
what and why are they innevervated by somatic motor nuerons
Skeletal muscle cannot contract spontaneosly
therefore, they are innervates by somaticmotor nuerons
what is innitiated in the meddulla oblangata
the innitation of contraction of the respirotory skeletal muscles
what is central pattern generattor
a network of neurons in the medulla oblangata, that have intrinsic rhythmic activity
what are the two nuclie in the medulla oblangata associated with respiration and what do they do
dorsal respiratory group (DRG) - inspiratory nuerons (ineurons)
- Control external intercostal muscles and diaphragm (muscles of inspiration)
ventral respiratory group (VRG) - expiration nuerons (Enuerone)
- control internal intercostals and abdominal muscles (active expiration)
what do chemoreceptors do?
what are the two sets of chemoreceptors respinsible for this
modify or adjust the rhythmicity of the central generator neurons
- Peripheral chemoreceptors
- central chemoreceptors
where are the peripheral chemoreceptors located
what does the peripheral chemoreceptors do
cartoi bodies - glomus cells
sence changes in PO2 and pH of plasma or increase in PCO2
tells what to do in terms of breathing to the medulla
what does decrease PO2 or decreased pH or increase in PCO2
more ventilation
what does plasma PO2 do before a signal is sent
change radically
where are teh central chemoreceptors located and what they do
located in medulla oblangata - most important chemical controller of ventilation
more PCO2 in arterial blood results in
more ventilation
how are the central chemoreceptors activated
CO2 crosses blood brain barrier into cerebrospinal fluid (CSF) - activates central chemoreceptors via changes in pH caused by he production of carbonic acid
CO2 + H2O -> H2CO3 - >HCO3- + H+
what does chemoreceptors do(H+)
sense changes of H+ in CSF and not H+ in arterial blood
what do mechanoreceptors do and what are the two types of them and where are they located
control ventilation to protect the lungs
- irramd receptors: airway mucosa
- stretch receptors: located in airway smooth muscle
wha do irrant receptors do
stimulation triggers parasympathetic neurons that innervate bronchilar smooth muscle - bronchoconstriction
