What are the components of the peripheral chemoreceptor system? (3)
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This is the termination of vagus and glossopharyngeal nerveNucleus of the Tractus Solitarius (NTS)This respiratory group limits the duration of inspiration.Pneumotaxic CenterThis respiratory group ⬆increases respiratory rate when stimulated Choices: (1) Dorsal respiratory group (2) Ventral respiratory group (3) Pneumotaxic centerPneumotaxic CenterLocation of Pneumotaxic centerupper pons The pneumotaxic center, located in the upper pons, sends inhibitory impulses to the inspiratory center, terminating inspiration, and thereby regulating inspiratory volume and respiratory rate.If ⬆increased pneumotaxic signal, There is: ⬆increase/⬇decrease_________ filling of lungs, shortens/prolongs________ inspiration, ⬇decreased/⬆increased_________ rate of breathing⬇ ⬇decreased, ⬇ shortens (< 0.5s) ⬆ ⬆increasedIf ⬇decreased pneumotaxic signal, ⬇decreased/⬆increased_________ filling of lungs, shortens/prolongs_________ inspiration, ⬇decreased/⬆increased_________ rate of breathing⬆ ⬆increased filling of lungs, ⬆prolongs inspiration, ⬇⬇decreased rate of breathingThis respiratory group remains almost totally inactive during normal quiet respiration.Ventral respiratory groupVentral respiratory group is found in (2)Nucleus ambiguus (rostrally), 💀 and nucleus RETROambiguus (caudally)This respiratory group has no significance during normal quiet breathing Choices: (1) Dorsal respiratory group (2) Ventral respiratory group (3) Pneumotaxic centerVentral respiratory groupIf there is a need for ⬆increased pulmonary ventilation, This group contribute for extra respiratory drive: Choices: (1) Dorsal respiratory group (2) Ventral respiratory group (3) Pneumotaxic centerVentral respiratory groupThis respiratory group functions in both inspiration and expiration Choices: (1) Dorsal respiratory group (2) Ventral respiratory group (3) Pneumotaxic centerVentral respiratory groupRespiratory groups: Inspiration, Expiration, BothInspiration: BOTH Dorsal and VENTRAL Expiration: Ventral Pneumotaxic center: for control of rate and depth of breathingThis reflex gives lung inflation signals that limit inspirationHering-Breuer Inflation ReflexHering-Breuer Inflation Reflex: Overstretching tk add moreStimulus for Hering-Breuer Inflation ReflexOverstretchingHering-Breuer inflation reflex is activated when tidal volume:____ L or how many times normalWhen tidal volume ⬆increases more than 3x normal (>= 1.5 L/breath)Hering-Breuer inflation reflex is protective mechanism for:preventing excess lung inflation, rather than an important ingredient in normal control of ventilationUltimate goal of respiration is to maintain proper concentrations of (3) ions to tissuesCO2, O2, and H+Respiratory activity is not/highly________ responsive to changes in O2, CO2, and H+highlyChemical control, which ions are important:CO2 and H+ only not really O2Excess CO2 and H+ act directly on ____; O2 acts almost entirely on _______ (found in carotid and aortic bodies)respiratory center; peripheral chemoreceptorsWhere are the peripheral chemoreceptors located?Carotid and aortic bodiesThe respiratory center is chemosensitive. They respond to changes in ____ or ____. They are also highly sensitive, meaning they can excite the other portions of the respiratory centerPCO2 and H+____ ions may be the only important direct stimulus for the sensory neurons (chemosensitive neuron)H+H+ can easily/cannot easily penetrate_______________ the blood-brain barriercannot penetrate easilyH+/CO2_______ have a potent indirect effect to the chemosensitive areaCO2. H+ has a DIRECT effect.CO2 + H2O ➡ _____ acid ➡ H+ + HCO3-. Which then dissociates when inside the Blood-brain Barrier. Thus having direct effectCarbonic Acid. H2CO3. H+ products from other reactions, not really easily cross. but CO2 canBlood CO2 has lesser/greater ______ potency in stimulating the respiratory center than Blood H+. *Blood H+ here means the H+ from other reactions not Carbonic acidIf change in PCO2 is greater than change in blood pH. There will be marked ⬆increase in ventilationChanges in PO2 have little/great _____ effect on the respiratory center to alter respiratory drivevirtually no direct effectWhich Receptors does Oxygen have an indirect effect?Peripheral chemoreceptorsPeripheral chemoreceptors are located inside/outside____ the brainoutsidePeripheral chemoreceptors are important for detecting changes in ______ in the blood. These chemoreceptors then transmit nervous signals to the _________ to regulate respiratory activity.Oxygen in the blood; Respiratory centersWhere are the majority of peripheral chemoreceptor systems located?Carotid bodies, Aortic bodies, and very few are located elsewhereCarotid bodies are found in the _____ of the common carotid arteriesBifurcationsCAROTID BODIES: Afferent nerve fibers pass through ____ nerves to the _____ nerves and then to the dorsal respiratory area of the medulla.Hering's Nerves to the Glossopharyngeal nerves.Aortic bodies are located along _______the arch of the aortaAORTIC BODIES: Afferent nerve fibers of the aortic bodies pass through the _____ and also to the dorsal respiratory area of the medolavagi(4) factors that stimulates peripheral chemoreceptors:(1) Arterial O2, (2) CO2 concentration, (3) , (4) Oxygen Deficiency 3 nalang oy di ko kakita sa ika upatImpulse rate of peripheral chemoreceptor system is particularly sensitive to changes in arterial PO2 (at 60 down to 30 mm Hg)If there is ⬇decrease in Arterial PO2> ⬆increase/⬇decrease ______ activity of carotid body⬆increaseThese values also corresponds to the range in which hemoglobin saturation with oxygen ⬇decreases rapidlyPeripheral chemoreceptors stimulation by CO2 occurs more/less rapidly as central stimulationMore rapidly, at 5xOxygen deficiency stimulates Peripheral Chemoreceptor system. Exact mechanism is still unknownhighly characteristic glandular-like cells, called __________, that synapse directly or indirectly with the nerve endings. Current evidence suggests that these __________ function as the chemoreceptors and then stimulate the nerve endings (Figure 42-6 ).Glomus cellsGlomus cells have O2 -sensitive ______________ that are inactivated/activated_______ when blood Po 2 decreases markedly. This inactivation/activation________ causes the cell to depolarize, which in turn opens voltage-gated calcium channels and increases intracellular calcium ion concentration.K channels; Inactivated, InactivationIf PO2 is greater than 100 mmHg, there is a none/major_______ effect on ventilationno effect on ventilationIf PO2 is less than 100 mmHg (60 mmHg), ventilation reduced to half/doubles ________. At Very very low PO2, ventilation may ⬆increase/⬇decrease _______ 5-foldventilation doubles, or ⬆increases five-fold at very low PO2Under low PO2 conditions, ________ drives breathing stronglylow arterial PO2Phenomenon of Acclimatization: Chronic breathing of ______ ➡ ⬇decrease/⬆increase _____ stimulation of respirationLow oxygen; ⬆increase stimulation of respirationInstead of the 70% ⬆increase in ventilation that might occur after acute exposure to low oxygen, the alveolar ventilation often ⬆increases _____ to ____ percent after 2-3 days of low oxygen.400-500%Thus, mountain climbers have to ascend slowly/fastly ________ to better adapt to the mountain. To give time for the lungs to adapt to the changesslowly_______ is a type of breathing disorder characterized by cyclical episodes of apnea and hyperventilation.Cheyne-Stokes Breathingis a type of abnormal breathing. It's characterized by a gradual ⬆increase in breathing, and then a ⬇decrease.Cheyne-Stokes BreathingCharacterized by slowly waxing and waning respiration occuring about every 40-60 sCheyne-Stokes BreathingAt normal condition and NOT cheyne-stokes breathing, the lungs CAN/CANNOT______ cause the next cycle of periodic breathing while the current one is ongoing.Cannot(2) conditions that can lead to Cheyne-Stokes breathing(1) Severe cardiac failure (⬇decreased blood flow), (2) brain damage (⬆increased negative feedback gain in the respiratory control areas)Low/High_________ compliance indicates a stiff lung (one with high elastic recoil) and can be thought of as a thick balloon - this is the case often seen in fibrosis. Low/High_________ compliance indicates a pliable lung (one with low elastic recoil) and can be thought of as a grocery bag - this is the case often seen in emphysema.Low; High