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AP II chp 23.2
Question | Answer |
---|---|
Respiratory and circulatory systems work together to regulate gas delivery by: | regulating ventilation;altering oxygen carrying capacity and affinity;altering perfusion |
What involves neurons in the reticular formation? | the medulla and pons |
Motor function:(control of respiration) | helps control coarse limb movements; reticular autonomic centers regulate visceral motor functions(vasomotor, cadiac, respiratory centers) |
Dorsal Respiratory Group (DRG) | inspiratory center |
functions of DRG | quiet and forced breathing |
Ventral Respiratory Group(VRG) | inspiratory and expiratory center |
functions of VRG | only in forced breathing - exercise |
Apneustic center | promotes inspiration by stimulation of the neurons in the medulla oblongata providing a CONSTANT STIMULUS |
Pontine respiratory group(PRG) | antagonises the apenustic center, cyclically inhibiting inspiration. This DECREASES tidal volume and REGULATES THE RESPIRATORY RATE |
Absence of the PRG results in an: | increase in depth of respiration and a decrease in respiratory rate |
Control areas are clusters of what kind of cells that are excitable? | neuronal cells |
What receptor is on aorta leaving the heart? | aortic chemoreceptors |
What receptor is on carotid arteries going to the brain? | carotid chemoreceptors |
What are the 5 sensory modifiers of respiratory center activities? | 1)chemoreceptors;2)baroreceptors;3)stretch receptors;4)irritating physical or chemical stimuli;5)other sensations |
Chemoreceptors of respiratory center activities are: | sensitive to PCO2, PO2 or pH of blood or cerebrospinal fluid |
Baroreceptors of respiratory center activities are: | in aortic or carotid sinuses are sensitive to changes in blood pressure |
stretch receptors of respiratory center activities: | respond to changes in lung volume |
irritating physical or chemical stimuli of respiratory center actitivies: | in nasal cavity, larynx or bronchial tree |
other sensations of respiratory center actitivities: | including pain, changes in body temperature, abnormal visceral sensations |
What is the cranial nerve IX? | GLOSSOPHARYNGEAL NERVE; from carotid bodies, stimulated by changes in blood pH or PO2 |
What is the cranial nerve X? | VAGUS NERVE; from aortic bodies,stimulated by changes in blood pH or PO2 |
Receptors monitoring CSF are: | on ventrolateral surface of medualla oblongata; respond to PCO2 and pH of CSF |
Glomus cells contain what kind of channels? | oxygen-gated K+ channels |
List the steps of oxygen-gated K+ channels | 1)oxygen sensor detects low PO2;2)closes K+ channels;3)cell DEPOLARIZES;4)causes release of DOPAMINE;5)stimulates sensory neuron |
list the mechanisms in central chemoreceptors | 1)CO2 CROSSES BLOOD/BRAIN BARRIER;2)carbonic anhydrase converts CO2 to HCO3- and H+;3)H+ stimulates receptor;4)stimulates ventilation |
Hypercapnia | an increase in arterial PCO2; stimulates chemoreceptors in the medulla oblongata |
Hypoventilation | a common cause of hypercapnia;ABNORMALLY LOW RESPIRATION RATE allows CO2 buildup in blood; aka:decrease breathing rate and depth |
hyperventilation | results in abnormally low PCO2(hypocapnia); stimulates chemoreceptors to decrease respiratory rate; aka:get rid of CO2, increase breathing rate and depth |