BMS 301 Exam #3 (Quiz Questions)
Which of the following would cause a decrease in the binding affinity of hemoglobin for oxygen? a. increased pH of the blood b. increased temperature of the blood c. decreased DPG levels in erythrocytes d. the presence of carbon monoxide e. decreased concentration of H+ in the blood
B
Which cells are associated with the structure of the alveolus and are therefore associated with the exchange of gases within the lungs?
Type 1 alv. cells
Myoglobin's affinity for oxygen is ____________ hemoglobin's affinity for oxygen.
greater than
Blood flow to the lungs is continuous in what zone?
zone 3
Under what conditions is lung compliance increased? a. respiratory distress syndrome of the newborn b. emphysema c. pneumothorax
B
Carbonic anhydrase catalyzes a reaction that combines which of the following? a. H2O and O2 b. H2O and CO2 c. H2O and CO d. H+ and HCO3- e. CO2 and O2
B
What brain center has neurons that fire mainly during inspiration and have input to the spinal motor neurons that activate the diaphragm and inspiratory intercostal muscles? a. the ventral respiratory group of the medulla oblongata b. the pre-Botzinger complex c. the dorsal respiratory group of the medulla oblongata d. the pneumotaxic center of the pons e. the apneustic center of the pons
C
Which of these correctly describes the chloride shift? a. In the lungs, chloride enters red blood cells in exchange for bicarbonate ions. b. In the tissues, chloride exits red blood cells in exchange for carbonic acid. c. In the tissues, chloride enters red blood cells in exchange for bicarbonate ions. d. In the lungs, chloride enters red blood cells in exchange for CO2. e. In the tissues, chloride enters red blood cells in exchange for CO2.
C
Which of these results from hyperventilation? a. increased alveolar PCO2 and decreased alveolar PO2 b. an increase in both alveolar PCO2 and PO2 Correct c. decreased alveolar PCO2 and increased alveolar PO2 d. a decrease in both alveolar PCO2 and PO2 the same alveolar PCO2 as under normal conditions
C
Following strenuous exercise, blood levels of lactate are ________ compared to pre-exercise levels. This change in acid concentration causes a reflex ________ in ventilation by activating ________. a. decreased; decrease; central chemoreceptors b. increased; increase; baroreceptors in the aortic arch c. increased; increase; central chemoreceptors d. increased; increase; peripheral chemoreceptors
D
t/f For the average healthy person, the pulmonary system is the major limiting factor for exercise performance.
false
t/f Infants born prematurely frequently develop respiratory distress syndrome of the newborn because they have too few alveoli to exchange O2 and CO2 efficiently.
false
t/f When standing, blood flow to the apex of the lung is greater than the base.
false
t/f During inhalation/inspiration, the diaphragm contracts and the alveolar pressure is less than atmospheric pressure; during exhalation/expiration, the diaphragm relaxes and the alveolar pressure is greater than atmospheric pressure.
true
t/f During light to moderate exercise, it is more efficient to increase the depth of breathing rather than the frequency
true
t/f Surfactant decreases the surface tension of the alveoli
true
t/f The larger the transpulmonary pressure, the more the lungs expand.
true
This center is believed to be important for activating muscles during forced expiration?
ventral respiratory group
