L15: Learning Quiz Q's Flashcards
What are the correct partial pressures for oxygen and carbon dioxide, respectively, in alveolar air?
160 mm Hg, 0.3 mm Hg
≤ 40 mm Hg, ≥ 46 mm Hg
40 mm Hg, 46 mm Hg
100 mm Hg, 40 mm Hg
100 mm Hg, 40 mm Hg
Which nerve provides innervation to the diaphragm?
sciatic nerve
intercostal nerve
vagus nerve
phrenic nerve
phrenic nerve
Which of the following is the respiratory control center that is believed to facilitate the transition between inspiration and expiration?
dorsal respiratory group (DRG)
ventral respiratory group (VRG)
central pattern generator (CPG)
pontine respiratory group (PRG)
pontine respiratory group (PRG)
The sensitivity of peripheral chemoreceptors for H+ is greatly increased when the arterial PO2 drops below which value?
75 mm Hg
60 mm Hg
46 mm Hg
80 mm Hg
60 mm Hg
In terms of the local control of the lungs, a low PO2 and high PCO2 causes
vasoconstriction and bronchodilation.
vasodilation and bronchodilation.
vasodilation and bronchoconstriction.
vasoconstriction and bronchoconstriction.
vasoconstriction and bronchodilation.
Which of the following statements regarding the effects of high altitude on blood gases and pH is incorrect?
Kidneys excrete bicarbonate to match the loss of hydrogen that accompanies a low PCO2.
Alveolar PO2 decreases in high altitude.
Polycythemia occurs.
Arterial PO2 increases in high altitude.
Arterial PO2 increases in high altitude.
A decrease in the pH of blood will:
inhibit peripheral chemoreceptors
increase the affinity of hemoglobin for oxygen
not affect the respiratory control center in the medulla
increase the rate of action potentials in the phrenic nerve
increase the rate of action potentials in the phrenic nerve
this controls the diaphragm which will causes it to breathe more, expelling more CO2 and depleting H+/protons concentration since equation will shift to the left
What could be an effect of hyperventilation?
hypoxia
acidosis
hypocapnia
apnea
hyperventilation is when there is increased air flow so the answer is hypocapnia, low co2 levels
The PO2 in George’s pulmonary veins is 99 mmHg, while the PO2 in George’s pulmonary arteries is 38 mmHg. Which of the following is most likely to be the PO2 in George’s tissues?
38 mmHg
61 mmHg
99 mmHg
160 mmHg
38 mmHg
Which of the following would decrease the transport of carbon dioxide in the blood?
decrease in PO2 in blood
inhibitor of carbonic anhydrase
increase in hemoglobin
enhanced chloride shift
inhibitor of carbonic anhydrase
This is due to (86-90%) of Co2 being converted to bicarbonate by carbonic anhydrase in RBC, then
transported in plasma. No CA, no transport.
Which of the following would result in increased inspiration?
Relaxation of diaphragm
Lactic acid produced during exercise
Increase in pH of cerebrospinal fluid
Increased activity of expiratory neurons
Lactic acid produced during exercise
