Review Questions Flashcards
Compounds that dissociate incompletely into H+ and a conjugate base are members of which of the following compounds? A. Strong acid B. Weak acid C. Strong base D. Weak base
•Weak acid
Which of the following buffer systems is most important in buffering renal tubular fluid? A. Phosphate B. Carbonate C. Bicarbonate D. Hemoglobin
•Phospate
Most bicarbonate reabsorption occurs in which of the following parts of renal tubule? A. Proximal tubule B. Descending limp of Henle C. ascending limb of Henle D. distal tubule
•proximal tubule
The bicarbonate buffer system consists of a bicarbonate salt and which of the following? A. weak acid B. strong acid C. weak base D. strong base
•Weak acid
Which of the following buffer system is the most important extracellular buffer system? A. phosphate B. carbonate C. bicarbonate D. hemoglobin
•Bicarbonate
Primary active H+ secretion involves a H-transporting ATPase. It occurs in which of the following parts of renal tubules?
A. descending limb of Henle
B. ascending limb of Henle
C. late distal tubules in intercalated cells
D. early collecting tubules in principle cells
•late distal tubules in intercalated cells
Which of the following occurs when a decrease in bicarbonate ion results in a decrease in the ration of bicarbonate to CO2 in the extracellular fluid? A. Respiratory acidosis B. Respiratory alkalosis C. Metabolic acidosis D. Metabolic alkalosis
•Metabolic acidosis
Respiratory alkalosis due to a decrease in CO2 concentration caused by hyperventilation is compensated for by which of the following mechanisms?
A. increased ventilation rates
B. decreased ventilation
C. Renal excretion of bicarbonate
D. Renal addition of new bicarbonate ion to extracellular fluild
•Renal excretion of bicarbonate ions
T/F Acidosis occurs when the ratio of bicarbonate ion to carbon dioxide in the extracellular fluid decreases. When this change is due to a decrease in bicarbonate, it is called respiratory acidosis.
•False, it should be metabolic
The volume by which the lungs and thorax increase for each unit of pressure change in the transpulmonary pressure is referred to as: A. Tidal volume B. Inspiratory pressure C. Compliance D. Transpumlonary volume E. Elasticity
•C, Compliance
During heavy exercise blood flow through the lungs increases four to seven times that at rest. This increase is due to which of the following?
A. Increase in the number of open capillaries up to three times normal
B. Distention of capillaries and a doubling in the flow rate
C. Increase in pulmonary arterial pressure
D. All the above
E. A and B only
•D, All the above
The Va/Q ratio is zero under which of the following conditions? A. Va = infinity, but Q = 1 B. Va = infinity, but Q = 0 C. Va = 0, but perfusion > 0 D. Va > 0, but Q = 0
•C
According to the oxygen-hemoglobin dissociating curve, an increase in blood partial oxygen pressure will have which of the following effects?
A. A decrease in bound oxygen
B. An increase in bound oxygen
C. No change in bound oxygen
D. There is no correlation between the two variables
•B, An increase in bound oxygen
Reduction of blood flow to a portion of the lung has which of the following effects?
A. Alveolar pCO2 is lowered, resulting in a constriction of the bronchi supplying that portion of lung.
B. Alveolar pCO2 is elevated, resulting in a constriction of the bronchi supplying that portion of the lung.
C. Alveolar pCO2 is lowered, resulting in a dilation of the bronchi supplying that portion of the lung.
D. Alveolar pCO2 is elevated, resulting in a constriction of the bronchi supplying that portion of the lung.
•A
One gram of hemoglobin can bind to how much oxygen? A. 19.4 ml B. 15.4 ml C. 3.25 ml D. 1.34 ml
•D, 1.34 ml oxygen
