Question 1

What is the partial pressure of oxygen in a gas mixture that is 40% oxygen, 40% argon, and 20% helium, when the total pressure of the gas is 1000 mm Hg?

Accepted Answer

A)  400 mm Hg
B)  600 mm Hg
C)  200 mm Hg
D)  100 mm Hg
E)  333 mm Hg

Question 2

What is the partial pressure of oxygen in air at sea level?

Accepted Answer

A)  160 mm Hg
B)  400 mm Hg
C)  60 mm Hg
D)  600 mm Hg
E)  210 mm Hg

Question 3

The majority of oxygen present within the blood is

Accepted Answer

A)  bound to plasma proteins.
B)  in the plasma as HCO3- .
C)  dissolved within the plasma.
D)  bound to hemoglobin in red blood cells.
E)  bound to hemoglobin within the plasma.

Question 4

Respiratory acidosis will result from a(n)

Accepted Answer

A)  decrease in blood CO2 concentration.
B)  increase in blood CO2 concentration.
C)  increase in carbon monoxide.
D)  increase in blood bicarbonate.
E)  decrease in blood bicarbonate.

Question 5

During active breathing, bursts of action potentials are observed to occur

Accepted Answer

A)  simultaneously in the inspiratory and expiratory motor neurons.
B)  synchronously in the inspiratory and expiratory motor neurons.
C)  asynchronously in the inspiratory and expiratory motor neurons.
D)  exclusively in the inspiratory motor neurons.
E)  exclusively in the expiratory motor neurons.

Question 6

In the lung, the uptake of oxygen is in part determined by the ventilation- perfusion ratio, which varies throughout the lung. Describe how ventilation- perfusion is regulated within the lung itself. How would ventilation- perfusion ratio be affected by hyperventilation?

Accepted Answer

The ratio of ventilation to perfusion is...

Question 7

Which of the following statements is FALSE regarding a leftward shift in the hemoglobin- oxygen dissociation curve?

Accepted Answer

A)  It can be caused by an increase in blood pH.
B)  Oxygen loading onto the hemoglobin is increased.
C)  It can be caused by an increase in PCO2.
D)  Affinity for oxygen is increased.
E)  Hemoglobin is more saturated at a given PO2.

Question 8

The presence of bicarbonate ions in the blood has an important direct effect, aside from the transport of CO2, that involves

Accepted Answer

A)  altering the activity of several receptors.
B)  stimulating the proliferation of alveolar epithelial cells.
C)  altering the activity of carbonic anhydrase.
D)  maintaining acid- base balance.
E)  altering the affinity of hemoglobin for oxygen.

Question 9

Within an erythrocyte, the conversion of CO2 to bicarbonate is prevented from reaching equilibrium by the

Accepted Answer

A)  presence of oxygen.
B)  temperature of the body.
C)  absence of a nucleus.
D)  presence of hydrogen ions.
E)  efflux of bicarbonate from the erythrocyte via the chloride shift.

Question 10

The solubility of oxygen in solution is relatively low, necessitating the presence of hemoglobin to carry oxygen to active tissues. Hemoglobin exhibits several unique characteristics that make it well suited for the transport of oxygen. Describe the structure of hemoglobin and the mechanisms that can alter the affinity of hemoglobin for oxygen.

Accepted Answer

Hemoglobin is composed of four subunits,...

Question 11

The central pattern generator is the rhythm generator that sets the background rhythm for ventilation. However, the respiratory system must be able to respond to changes that require either increases or decreases in ventilation. Describe the receptors that are involved in modulating ventilation and how they function.

Accepted Answer

There are a number of receptors involved...

Question 12

In the discussion of respiration, hydrogen ions were shown to be important in many aspects of ventilation. Thus, the respiratory system plays an important role in the regulation of acid- base balance. Describe the role of the respiratory system in the maintenance of acid- base balance.

Accepted Answer

Typically, blood pH is somewhere around ...

Question 13

Breathing involves the interaction between a number of the control centers of ventilation. Describe the model that has been developed to describe the process of quiet breathing, including how volume of the lung is altered by this process.

Accepted Answer

The model for quiet breathing involves t...

Question 14

The Haldane effect describes the increase in the affinity of hemoglobin for CO2 in the presence of a lowered

Accepted Answer

A)  concentration of bicarbonate (HCO3- ) .
B)  PO2.
C)  temperature.
D)  PCO2.
E)  pH.

Question 15

Which statement best describes the cause of decompression sickness?

Accepted Answer

A)  Carbon dioxide bubbles come out of solution too quickly and burst blood vessels, especially in the brain.
B)  Oxygen molecules are so tightly compressed due to pressure exerted by the water column that they cannot deliver oxygen to the tissues.
C)  The oxygen molecule expands upon ascent and bursts, therefore causing a lack of oxygen to the tissues.
D)  Carbon dioxide is driven into the cardiovascular system and causes acidosis.
E)  Nitrogen gas bubbles form in the blood, joints, and nervous system as pressure decreases from too fast an ascent.

Question 16

Pulmonary edema describes a condition where the uptake of oxygen and unloading of carbon dioxide is reduced as a consequence of a(n)

Accepted Answer

A)  thickening of the diffusion barrier by fluid accumulation in the pulmonary blood.
B)  increase in the partial pressure of oxygen in the blood.
C)  thickening of the diffusion barrier by fluid accumulation in the alveoli.
D)  decrease in the partial pressure of oxygen in the alveolus.
E)  decrease in the partial pressure of carbon dioxide in the alveolus.

Question 17

Movement of oxygen and carbon dioxide between alveoli and blood occurs by what process?

Accepted Answer

A)  facilitated diffusion
B)  simple diffusion
C)  osmosis
D)  primary active transport
E)  secondary active transport

Question 18

A majority of the control of ventilation resides within the central nervous system. Identify the regions of the brain that are important in the regulation of ventilation and how each of them functions in the control of ventilation.

Accepted Answer

there is a...

Question 19

Hemoglobin has a greater affinity for oxygen in the lungs than it does in respiring tissue.

Accepted Answer

A) True 
 B)False

Question 20

Which of the following causes a decrease in the PO2 of air as it enters the conducting zone of the lungs?

Accepted Answer

A)  the increasing PCO2
B)  decreasing alveolar PO2
C)  warming of the air
D)  the consumption of oxygen
E)  humidifying the air

Exam 17: The Respiratory System: Gas Exchange and the Regulation of Breathing

Movement of oxygen and carbon dioxide between alveoli and blood occurs by what process?

Correct Answer
verified

What is the partial pressure of oxygen in air at sea level?

Correct Answer
verified

Respiratory acidosis will result from a(n)

Correct Answer
verified

Which of the following causes a decrease in the PO2 of air as it enters the conducting zone of the lungs?

Correct Answer
verified

Correct Answer
verified
There are a number of receptors involved...
View Answer

Pulmonary edema describes a condition where the uptake of oxygen and unloading of carbon dioxide is reduced as a consequence of a(n)

Correct Answer
verified

Correct Answer
verified
Hemoglobin is composed of four subunits,...
View Answer

In the discussion of respiration, hydrogen ions were shown to be important in many aspects of ventilation. Thus, the respiratory system plays an important role in the regulation of acid- base balance. Describe the role of the respiratory system in the maintenance of acid- base balance.

Correct Answer
verified
Typically, blood pH is somewhere around ...
View Answer

Which of the following statements is FALSE regarding a leftward shift in the hemoglobin- oxygen dissociation curve?

Correct Answer
verified

Breathing involves the interaction between a number of the control centers of ventilation. Describe the model that has been developed to describe the process of quiet breathing, including how volume of the lung is altered by this process.

Correct Answer
verified
The model for quiet breathing involves t...
View Answer

During active breathing, bursts of action potentials are observed to occur

Correct Answer
verified

The majority of oxygen present within the blood is

Correct Answer
verified

In the lung, the uptake of oxygen is in part determined by the ventilation- perfusion ratio, which varies throughout the lung. Describe how ventilation- perfusion is regulated within the lung itself. How would ventilation- perfusion ratio be affected by hyperventilation?

Correct Answer
verified
The ratio of ventilation to perfusion is...
View Answer

Within an erythrocyte, the conversion of CO2 to bicarbonate is prevented from reaching equilibrium by the

Correct Answer
verified

Hemoglobin has a greater affinity for oxygen in the lungs than it does in respiring tissue.

Correct Answer
verified

What is the partial pressure of oxygen in a gas mixture that is 40% oxygen, 40% argon, and 20% helium, when the total pressure of the gas is 1000 mm Hg?

Correct Answer
verified

A majority of the control of ventilation resides within the central nervous system. Identify the regions of the brain that are important in the regulation of ventilation and how each of them functions in the control of ventilation.

Correct Answer
verified
there is a...
View Answer

The Haldane effect describes the increase in the affinity of hemoglobin for CO2 in the presence of a lowered

Correct Answer
verified

Which statement best describes the cause of decompression sickness?

Correct Answer
verified

The presence of bicarbonate ions in the blood has an important direct effect, aside from the transport of CO2, that involves

Correct Answer
verified

Exam 17: The Respiratory System: Gas Exchange and the Regulation of Breathing

Movement of oxygen and carbon dioxide between alveoli and blood occurs by what process?

Correct AnswerverifiedShow Answer

What is the partial pressure of oxygen in air at sea level?

Correct AnswerverifiedShow Answer

Respiratory acidosis will result from a(n)

Correct AnswerverifiedShow Answer

Which of the following causes a decrease in the PO2 of air as it enters the conducting zone of the lungs?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedThere are a number of receptors involved...View AnswerShow Answer

Pulmonary edema describes a condition where the uptake of oxygen and unloading of carbon dioxide is reduced as a consequence of a(n)

Correct AnswerverifiedShow Answer

Correct AnswerverifiedHemoglobin is composed of four subunits,...View AnswerShow Answer

In the discussion of respiration, hydrogen ions were shown to be important in many aspects of ventilation. Thus, the respiratory system plays an important role in the regulation of acid- base balance. Describe the role of the respiratory system in the maintenance of acid- base balance.

Correct AnswerverifiedTypically, blood pH is somewhere around ...View AnswerShow Answer

Which of the following statements is FALSE regarding a leftward shift in the hemoglobin- oxygen dissociation curve?

Correct AnswerverifiedShow Answer

Breathing involves the interaction between a number of the control centers of ventilation. Describe the model that has been developed to describe the process of quiet breathing, including how volume of the lung is altered by this process.

Correct AnswerverifiedThe model for quiet breathing involves t...View AnswerShow Answer

During active breathing, bursts of action potentials are observed to occur

Correct AnswerverifiedShow Answer

The majority of oxygen present within the blood is

Correct AnswerverifiedShow Answer

In the lung, the uptake of oxygen is in part determined by the ventilation- perfusion ratio, which varies throughout the lung. Describe how ventilation- perfusion is regulated within the lung itself. How would ventilation- perfusion ratio be affected by hyperventilation?

Correct AnswerverifiedThe ratio of ventilation to perfusion is...View AnswerShow Answer

Within an erythrocyte, the conversion of CO2 to bicarbonate is prevented from reaching equilibrium by the

Correct AnswerverifiedShow Answer

Hemoglobin has a greater affinity for oxygen in the lungs than it does in respiring tissue.

Correct AnswerverifiedShow Answer

What is the partial pressure of oxygen in a gas mixture that is 40% oxygen, 40% argon, and 20% helium, when the total pressure of the gas is 1000 mm Hg?

Correct AnswerverifiedShow Answer

A majority of the control of ventilation resides within the central nervous system. Identify the regions of the brain that are important in the regulation of ventilation and how each of them functions in the control of ventilation.

Correct Answerverifiedthere is a...View AnswerShow Answer

The Haldane effect describes the increase in the affinity of hemoglobin for CO2 in the presence of a lowered

Correct AnswerverifiedShow Answer

Which statement best describes the cause of decompression sickness?

Correct AnswerverifiedShow Answer

The presence of bicarbonate ions in the blood has an important direct effect, aside from the transport of CO2, that involves

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
There are a number of receptors involved...
View Answer

Correct Answer
verified

Correct Answer
verified
Hemoglobin is composed of four subunits,...
View Answer

Correct Answer
verified
Typically, blood pH is somewhere around ...
View Answer

Correct Answer
verified

Correct Answer
verified
The model for quiet breathing involves t...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
The ratio of ventilation to perfusion is...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
there is a...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified