Deck 4: The Diffusion of Pulmonary Gases

Question 1

Which gas law is the law of partial pressures?

A) Graham's law
B) Dalton's law
C) Henry's law
D) Boyle's law

Answer 1

B

Question 2

What is the partial pressure of nitrogen if the barometric pressure is 760 mm Hg?

A) 592.8 mm Hg
B) 500.4 mm Hg
C) 420 mm Hg
D) 625.6 mm Hg

Answer 2

A

Question 3

What does the PH₂O equal in alveolar gas if the F_IO₂ is 0.21?

A) 573 mm Hg
B) 47 mm Hg
C) 40 mm Hg
D) 100 mm Hg

Answer 3

B

Question 4

At sea level, what would the P_AO2 equal if the P_B is 760 mm Hg, the PaCO2 is 40 mm Hg with F_IO₂ 1.0?

A) 673 mm Hg
B) 573 mm Hg
C) 100 mm Hg
D) 600 mm Hg

Question 5

What percentage of the atmosphere does carbon dioxide compose?

A) 0.003%
B) 0.03%
C) 3%
D) 0.3%

Question 6

What percentage of the atmosphere does oxygen compose?

A) 58%
B) 21%
C) 46%
D) 29%

Question 7

Which gas law states that the total pressure exerted by a mixture of gases is equal to the sum of the pressures exerted by each gas in the mixture?

A) Boyle's
B) Graham's
C) Dalton's
D) Henry's

Question 8

When breathing room air, what is the P_N2 in the arterial blood?

A) 573 mm Hg
B) 700 mm Hg
C) 593 mm Hg
D) 473 mmHg

Question 9

What would the partial pressure of oxygen equal in an air mixture at a depth of 99 feet under water?

A) 159 x 2 or 318 mm Hg
B) 159 x 4 or 636 mm Hg
C) 159 mm Hg
D) 159 x 3 or 477 mm Hg

Question 10

What is derived from the following equation? X = [P_B -P_H20] F_IO2 - PaCO2 (1.25)

A) P_ACO2
B) P_N2
C) P_AO2
D) PaO2

Question 11

What is the normal value for the respiratory exchange ratio?

A) 0.6
B) 1.0
C) 0.8
D) 1.25

Question 12

At sea level, what does the total atmosphere equal in mmHg?

A) 100 mm Hg
B) 159 mm Hg
C) 760 mm Hg
D) 593 mm Hg

Question 13

What is the term for the movement of gas molecules from an area of high pressure to an area of low pressure?

A) dispersion
B) ventilation
C) diffusion
D) osmosis

Question 14

Which gas law is represented by P_total = P₁ + P₂ + P₃....?

A) Boyle's
B) Dalton's
C) Charles'
D) Henry's

Question 15

What is absolute humidity of alveolar gas?

A) 21 mg/L
B) 44 mg/L
C) 47 mg/L
D) 40 mg/L

Question 16

What is the definition of molecular water?

A) water in the solid form
B) water in either gaseous or liquid form
C) water in the gaseous form
D) water in the gaseous form

Question 17

When breathing F_IO₂ 1.0 at sea level, what would the P_N2 in the alveoli equal?

A) 0
B) 593 mm Hg
C) 573 mm Hg
D) 47 mm Hg

Question 18

What accounts for the change in PO₂ between the atmosphere and alveoli?
I. Water vapor pressure in alveolar gas
II. PCO₂ is higher in alveolus than in the atmospheric gas
III. Higher percentage of N₂ in alveolar gas
IV. P_B is lower in the alveoli than in the atmosphere

A) I, II, and IV only
B) I and IV only
C) I and II only
D) I, II, III, and IV

Question 19

What effect does an increased altitude have on the percentage that gases compose in the atmosphere?

A) the percentages remain the same but the partial pressures would decrease with altitude
B) the partial pressures remain the same but the percentages would decrease
C) the percentages and the partial pressures would increase
D) the percentages and the partial pressures would decrease

Question 20

In the ideal alveolar gas equation, what does 1.25 represent?

A) correction factor for variations in respiratory exchange ratio
B) correction factor for variations in barometric pressure
C) correction factor for variations in water vapor pressure
D) correction factor for variations in FIO2

Question 21

In a healthy individual at rest, what is the average carbon dioxide tension of venous content blood as it enters the pulmonary capillary?

A) 35 mm Hg
B) 46 mm Hg
C) 27 mm Hg
D) 40 mm Hg

Question 22

In a healthy adult at rest, what duration is required for diffusion of oxygen and carbon dioxide across the alveolary capillary membrane to be complete?

A) 0.075 sec.
B) 0.075 sec
C) 0.75 sec
D) 0.25 sec

Question 23

For a healthy adult at rest, what is the normal pressure gradient for oxygen across the alveolar-capillary membrane when breathing room air at sea level?

A) 60 mm Hg
B) 40 mm Hg
C) 46 mm Hg
D) 6 mm Hg

Question 24

In order, what are the first three layers of the alveolar capillary membrane that an oxygen molecule crosses?
I. Liquid lining the intra-alveolar membrane
II. Alveolar epithelial cell
III. Basement membrane of the alveolar epithelial cell
IV. Interstitial space

A) I, III, and IV
B) I, II and III
C) II, II, IV
D) I, II and IV

Question 25

When can the simplified alveolar gas equation be used?
I. PaCO₂ less than 60 mm Hg
II. PaCO₂ greater than 60 mm Hg
III. FIO₂ 0.6 or greater
IV. FIO₂ 0.6 or lower

A) I only
B) II and IV only
C) II only
D) I and III only

Question 26

In a healthy adult at rest at sea level, what is the normal carbon dioxide gradient across the alveolar capillary membrane?

A) 40 mm Hg
B) 60 mm Hg
C) 27 mm Hg
D) 6 mm Hg

Question 27

What is the term for the passive movement of gas molecules from a high partial pressure to an area of low partial pressure until equilibrium is reached?

A) pressure gradient
B) osmosis
C) diffusion
D) active transport

Question 28

What is the solubility of oxygen at 760 mm Hg and 37 ° C?

A) 0.592 mL/mm Hg/ mL H2O
B) 0.25 mL/mm Hg/mL H2O
C) 0.75 mL/mm Hg/mL H2O
D) 0.0244 mL/mm Hg/mL H2O

Question 29

Why is supplemental oxygen indicate when acute alveolar inflammation is superimposed on chronic interstitial lung disease?

A) Diffusion is indirectly related to thickness of the a-c membrane and directly related to the pressure gradient (P1-P2) so diffusion will be enhanced with supplemental O2
B) Diffusion is indirectly related to thickness of the a-c membrane and indirectly related to the pressure gradient (P1-P2) so diffusion will be enhanced with supplemental O2
C) Diffusion is directly related to thickness of the a-c membrane and indirectly related to the pressure gradient (P1-P2) so diffusion will be enhanced with supplemental O2
D) Diffusion is directly related to thickness of the a-c membrane and directly related to the pressure gradient (P1-P2) so diffusion will be enhanced with supplemental O2

Question 30

Under normal resting conditions, what is the total transit time required for blood to move through the alveolar capillary system?

A) 0.25 seconds
B) 0.75 seconds
C) 1 second
D) 0.5 seconds

Question 31

Which law is represented by the equation below? V gas = [AD (P1-P2)] / T

A) Henry's law
B) Fick's law
C) Dalton's law
D) Boyle's law

Question 32

What are the middle three layers (4-5-6) that an oxygen molecule must cross when moving from the alveoli into the blood?

A) interstitial space, basement membrane of the capillary endothelium, and the capillary endothelium
B) interstitial space, basement membrane of the capillary endothelium, and the capillary endothelium
C) plasma of the capillary blood, the erythrocyte membrane, and the intracellular fluid in the erythrocyte.
D) the liquid lining the intra-alveolar membrane, alveolar epithelial cell, and the basement membrane of the alveolar epithelial cell

Question 33

How is oxygen diffusion affected when pulmonary edema is present?

A) Diffusion is directly related to thickness of the a-c membrane so diffusion will increase
B) Diffusion is indirectly related to thickness of the a-c membrane so diffusion will decrease
C) Diffusion is indirectly related to the thickness of the a-c membrane so diffusion will increase
D) Diffusion is directly related to the thickness of the a-c membrane so diffusion will decrease

Question 34

Which of the following are central nervous system effects associated with oxygen toxicity?
I. Tremors
II. Twitching
III. Convulsions
IV. Coma

A) III and IV only
B) I, II, and IV only
C) I, II, III, and IV
D) I, II, and III only

Question 35

Which law states that the amount of gas that dissolves in a liquid is directly related to the partial pressure of the gas?

A) Dalton's
B) Fick's
C) Henry's
D) Graham's

Question 36

What are the final three layers (7-8-9) that an oxygen molecule must cross when moving from the alveoli into the blood?

A) the liquid lining the intra-alveolar membrane, alveolar epithelial cell, and the basement membrane of the alveolar epithelial cell
B) interstitial space, basement membrane of the capillary endothelium, and the intracellular fluid of the erythrocyte
C) plasma of the capillary blood, the erythrocyte membrane, and the intracellular fluid in the erythrocyte.
D) the interstitial space, basement membrane of the capillary endothelium, and the capillary endothelium

Question 37

Which of the following are pulmonary effects associated with oxygen toxicity?
I. Tracheobronchitis
II. Substernal chest pain
III. Increased lung compliance
IV. Increased TLC

A) III and IV only
B) III and IV only.
C) I, II, and IV only
D) I and II only

Question 38

Which of the following pulmonary disorders cause the alveolar-capillary membrane thickness to increase?
I. Pulmonary edema
II. Scleroderma
III. ARDS
IV. Pneumonia

A) I and II only
B) I and IV only
C) I, III and IV only
D) I, II, III, and IV

Question 39

Which of the following conditions are indications for HBOT?
I. Clostridial gangrene
II. Intracranial abscess
III. Radiation necrosis
IV. Refractory osteomyelitis

A) I, II, III, and IV
B) I, III, and IV only
C) I and IV only
D) II and III only

Question 40

What is the normal thickness of the alveolar capillary membrane?

A) 0.36 - 2.5 mm
B) 2.6 - 3.5 mm
C) 0.36 - 2.5 microns
D) 2.6 - 3.6 microns

Question 41

Which gas is used to test the physiologic effectiveness of the alveolary-capillary membrane?

A) N2O
B) O2
C) CO
D) CO2

Question 42

Which of the following is true related to oxygen diffusion?

A) It can only be perfusion limited
B) It is normally diffusion limited but under certain abnormal pulmonary condition can become perfusion limited
C) It can only be diffusion limited
D) It is normally perfusion limited but under certain abnormal pulmonary conditions can become diffusion limited

Question 43

How do the rates of diffusion of CO2 and O2 compare?

A) CO2 diffuses 10 times faster than O2
B) O2 diffuses 10 times faster than CO2
C) O2 diffuses 20 times faster than CO2
D) CO2 diffuses 20 times faster than O2

Question 44

What is described by the following: "the movement of gas across the alveolar wall is a function of the integrity of the alveolar-capillary membrane'?

A) perfusion limited
B) perfusion
C) diffusion limited
D) diffusion

Question 45

What is the classic diagnostic sign that verifies that a patient has emphysema rather than other types of chronic obstructive disorders?

A) increased RV
B) decreased DLCO
C) increased FRC
D) decreased FEV₁

Question 46

What is the normal diffusion capacity of CO?

A) 60 mL/min/mmHg
B) 20 mL/min/mm Hg
C) 40 mL/min/mmHg
D) 25 mL/min/mm Hg

Question 47

What is the term for the situation in which "the rate of gas transfer across the alveolar wall is a function of the amount of blood that flows past the alveoli" ?

A) diffusion limited
B) penduluft
C) diffusion
D) perfusion limited

Question 48

Which law states that the rate of diffusion of a gas through the liquid is directly proportional to the solubility coefficient of the gas and inversely proportional to the square root of the GMW of the gas?

A) Henry's law
B) Dalton's law
C) Graham's law
D) Fick's law

Question 49

Which of the following conditions reduce the alveolar surface area?
I. Emphysema
II. Excessive airway secretions
III. Pneumothorax
IV. Sinusitis

A) I, II, and III only
B) I and III only
C) I only
D) I, II, III, and IV