Chapter 21: Respiratory Function and Alterations in Gas Exchange

Chapter 21: Respiratory Function and Alterations in Gas Exchange

Complete Chapter Questions With Answers

Sample Questions Are Posted Below

MULTIPLE CHOICE
1. The amount of gas remaining in the lungs after a maximal expiration is called the
a. residual volume.
b. functional residual capacity.
c. expiratory reserve volume.
d. vital capacity.
ANS: A
Residual volume is the amount of gas remaining in the lungs after a maximal expiration. Functional residual capacity is the amount
of gas left in the lungs at the end of a normal expiration. Expiratory reserve volume is the amount of gas expired beyond tidal
volume. Vital capacity is the total volume of gas that can be exhaled during maximal expiration.
REF: Pg. 459
2. An increase in filtration of fluid from the pulmonary capillaries into the interstitium occurs with ________ pressure.
a. increased capillary colloid
b. increased capillary hydrostatic
c. decreased capillary hydrostatic
d. decreased interstitial colloid
ANS: B
When capillary hydrostatic pressure exceeds capillary colloid osmotic pressure, fluid moves from the capillary to the interstitium.
Increased capillary colloid pressure, decreased capillary hydrostatic pressure, or decreased interstitial colloid pressure would all
prevent fluid movement out of the capillaries.
REF: Pg. 456
3. The central chemoreceptors for respiratory control are
a. located in the carotid artery.
b. responsive primarily to changes in pH and CO2.
c. responsive primarily to hypoxemia.
d. less important than the peripheral chemoreceptors in maintaining respiration.
ANS: B
Central chemoreceptors for respiratory control are responsive primarily to changes in pH and CO2. The central chemoreceptors are
located in the medullary center, are responsive to pH and CO2, and are more important than the peripheral chemoreceptors in
controlling respirations.
REF: Pg. 461
4. The peripheral chemoreceptors
a. are located in the medulla oblongata.
b. lead to hypoventilation when stimulated.
c. respond to the arterial oxygen level.
d. are unresponsive to pH and CO2 levels.
ANS: C
The peripheral chemoreceptors respond to reduced arterial oxygen (hypoxemia). The peripheral chemoreceptors are located in the
aortic arch and carotid bodies, lead to hyperventilation when stimulated, and respond to pH and CO2 levels in addition to arterial
oxygen level.