Respiratory Physiology Flashcards
(200 cards)
1
Q
Which of the following does NOT belong to the lower airway? A. Trachea B. Alveoli C. Larynx D. None of the above
A
C. Larynx
2
Q
In the trachea, C-shaped cartilages are found. Explain.
A
Trachea has a c-shaped cartilage in a way that when you swallow, esopagus compresses the posterior part of the trachea (non-cartilagenous part of the trachea) thus preventing aspiration of food particles or fluid into the lower airways.
3
Q
What is the correct sequence of the tracheobronchial tree?
A. trachea-mainstem bronchi-segmental bronchi-lobar bronchi-bronchioles-alveoli
B. trachea-mainstem bronchi-lobar bronchi-segmental bronchi-bronchioles-alveoli
C. trachea-mainstem bronchi-lobar bronchioles-segmental bronchioles-bronchioles-alveoli
D. Trachea-bronchioles-mainstem bronchi-lobar bronchi-segmental bronchi-alveoli
A
B. trachea-mainstem bronchi-lobar bronchi-segmental bronchi-bronchioles-alveoli
4
Q
Which of the following is NOT a characteristic of the right bronchi? A. Wider B. Shorter C. more vertical D. none of the above
A
D. None of the above. (Rationale: Right bronchi is wider, shorter and more vertical than the left bronchi which is narrower, wider and more horizontal)
5
Q
In foreign body aspiration, the most common site of aspiration in an upright postion is into the _______? A. Left Bronchi B. Left Bronchioles C. Right Bronchi D. Right Bronchioles
A
C. Right Bronchi
6
Q
Where does gas exchange occur? A. Mainstem bronchi B. segmental bronchi C. Terminal bronciole D. Respiratory bronchiole
A
D. Respiratory bronchiole
7
Q
Which of the following is TRUE about Goblet cells? A. May play a role in epithelial regeneration after injury B. Produces mucus C. For gas exchange D. For production of lung surfactant
A
B. Produces Mucus (Rationale: A. is for Clara cells; C. is for Type I pneumocytes D. is for Type II Pneumocytes)
8
Q
Which of the following is TRUE? A. Type I pneumocyte is more numerous than Type II B. Type II pneumocyte is more numerous than Type I C. Both D. Neither
A
D. Neither (Rationale: Type I and type II pneumocytes is the same in number)
9
Q
Which of the following is NOT TRUE about sneeze reflex? A. Without depression of uvula B. Very quick C. It is a protective function D. With depression of uvula
A
A. without depression of uvula (Rationale: It is in cough reflex that we have absence of the depression of uvula. In sneeze reflex, depression of uvula is present)
10
Q
The left lung contains: A. 3 lobes B. 2 lobes C. Horizontal Fissure D. Both A and C E. Both B and C
A
B. 2 lobes (Rationale: Lungs has 2 lobes and an Oblique fissure while the right lung has 3 lobes and has an oblique and horizontal fissure)
11
Q
Which of the following is NOT true about pleural fluid? A. It is found in a potential space between the parietal pleura and fascia B. It has negative pressure C. It keeps the 2 pleura together D. It allows the 2 pleura to slide with one another
A
A. It is found in a potential space between the parietal pleura and fascia. (Rationale: It is found in a potential space between the parietal pleura and VISCERAL PLEURA)
12
Q
Which of the following best describes Pleural effusion? A. Presence of air in the pleural space B. Presence of pus in the pleural space C. Presence of excess fluid in the pleural space D. All of the above
A
C. Presence of excess fluid in the pleural space (Rationale: A. is for Pneumothorax, B. is for Emphyema)
13
Q
A puncture in the thoracic cavity may result to introduction of air into the pleural space. What is this condition? A. Pneumothorax B. Pleural Effusion C. Empyema D. Abcess
A
A. Pneumothorax (Rationale: B. Pleural Effusion refers to the accumulation of excess fluid in the pleural space. C. Emphyema refers to the accumulation of pus in the pleural spac. D. Abcess is the term used to describe presence of pus in a normal space.)
14
Q
What is the ratio Type I pneumocytes and type II pneumocytes in the alveoli in terms of number? A. 1:2 B. 2:1 C. 1:1 D. 2:2
A
C. 1:1 (Rationale: Type I and Type II pneumocytes is the same in number but differ in extent of the surface area occupied in the alveoli because Type I pneumocyte is larger than Type II. 96-98% for Type I penumocyte, 2-4% for type II pneumocytes)
15
Q
The surfactant _______ surface tension. A. Increases B. Decreases C. does not affect
A
B. Decreases. (Rationale: Surface tension is the force exerted by the water molecules at the air-liquid interface that decreases the surface area. Surfactant are ampiphatic molecules that contains DPPC that breaks the hydrogen bond in between water molecules thus resulting in decreased surface tension)
16
Q
__________ explains how surface tension and alveolar radius affects the collapsing pressure of the alveoli. A. Poiseuille formula B. Law of Laplace C. Bernoulli’s Principle D. None of the above
A
B. Law of Laplace (P=2T/r where P=collapsing pressure in alveolus; T=surface tension and r=alveolar radius)
17
Q
Which of the following is TRUE regarding collapsing pressure? A. The greater the alveolar radius the greater collapsing pressure B. The lesser the alveolar radius the greater collapsing pressure C. The greater the surface tension the lesser ccollapsing pressureD. The lesser the surface tension the greater collapsing pressure
A
B. The lesser the alveolar radius the greater collapsing pressure (Rationale: Law of Laplace states that P=2T/r. Surface tension has a direct relationship with collapsing pressure, while alveolar radius has an inverse relationship with the collapsing pressure)
18
Q
What is the active component of pulmonary surfactant? A. H20 B. DPPC C. Phosphatidyl glycerol D. Calcium ions
A
B. DPPC
19
Q
What is the major component of pulmonary surfactant? A. H20 B. DPPC C. Phosphatidyl glycerol D. Calcium ions
A
A. H2O
20
Q
Increase pulmonary surfactant causes increase in lung compliance. A. True B. False
A
A. True (Rationale: Increase in surfactant reduces surface tension therefore increasing lung compliance)
21
Q
It is the capacity of an alveoli to exert traction on other surrounding alveoli to prevent collapse. A. Interdependence B. Collapsing Pressure C. Surface Tension D. None of the above
A
A. Interdependence
22
Q
It connects the terminal airway to adjacent alveoli. A. Pores of Kohn B. Canals of lambert C. Pneumocyte I D. Pneumocyte II
A
B. Canals of Lambert
23
Q
_________ limits lung distensibility. A. Collagen B. Elastin C. Cartilage D. Smooth Muscles
A
A. Collagen (Rationale: B. Elastin contributes to elastic recoil of the lungs, C. Cartilage supports conducting airways and D. Smooth muscles dilate or constrict airways.
24
Q
It is the blood supply of the lungs that carries oxygenated blood to the lungs. A. Bronchial circulation B. Pulmonary Circulation C. Both D. None of the above
A
A. Bronchial Circulation (Rationale: B. Pulmonary circulation carries deoxygenated blood to the lungs)
25
In a state of hypoxia, the pulmonary arterioles respond by: A. Constriction B. Dilatation
A. Constriction. "All arterioles responds to hypoxia by vasodilating except for PULMONARY ARTERIOLES, where it vasoconstricts to shunt blood to an area with greater oxygenation"
26
An increase in the Pulmonary Capillary pressure signifies: A. Decrease in Left atrial pressure B. Decrease in Right atrial pressure C. Increase in Left atrial pressure D. Increase in Right atrial pressure
C. Increase in left atrial pressure. (Rationale: Pulmonary Capillary wedge pressure(PCWP) estimates atrial pressure therefore an increase in Left atrial pressure increases PCWP and vice versa. If there is an increase in Left Atrial pressure, pulmonary capillary pressure also increases in order to facilitate a forward flow of the blood from pulmonary capillaries to the left atrium. Remember that blood flows from an area with higher pressure to an area with a lower pressure to ensure adequate blood flow)
27
Which of the following lung zones has a greater local alveolar pressure than alveolar air pressure throughout the cycle? A. Zone 1 B. Zone 2 C. Zone 3 D. Zone 4
C. Zone 3 (Rationale: A. Zone 1 has ACP Alveolar air pressure but less than that during diastole; and D. There is no zone 4)
28
Which of the following zone has NO blood flow? A. Zone 1 B. Zone 2 C. Zone 3 D. Zone 4
A. Zone 1
29
Which has the greatest ventilation? A. Base of the lungs B. Apex of the Lungs C. Middle portion of the Lungs
A. Base (Base has the highest ventilation and perfusion BUT the Apex has the greatest Ventilation-Perfusion ratio)
30
What is the MAJOR MUSCLE OF RESPIRATION? A. SCM B. Alae Nasi C. Genioglossus D. Diaphragm
D. Diaphragm (RATIONALE: The diaphragm is the major muscle of respiration and it divides the thoracic covaity from the abdominal cavity. During contraction it forces the abdominal contents to move downward and forward. This increases the vertical dimension of the chest cavity and creates a pressure difference bet. the thorax and abdomen. Reference Berne& Levy Physiology 6th Ed. Chap. 20 p.425)
31
Which of the following vertebral segments when injured will result to a complete dependency of the patient on a ventilator in order to breathe? A. T4-T6 B. L1-L3 C. C3-C5 D. S1-S3
C. C3-C5 (RATIONALE: The diaphragm is innervated by the right and left phrenic nerves, which have their origins at the 3rd to 5th cervical vertebral segments of the spinal cord. Reference Berne & Levy Physiology 6th ed. Chap. 20 p. 425)
32
TRUE OR FALSE. Paralysis of the external intercostal muscle will have a significant effect on respiration.
FALSE. (RATIONALE: Respiration is primarily dependent on the diaphragm which is innervated by the phrenic nerve that originates from C3-C5. Innervation of the external intercostal muscle originated from the intercostal nerves that arise from the same level of the spinal cord. Reference Berne & Levy Physiology 6th ed. Chap. 20 p. 425)
33
On contraction of the diaphragm, it protrudes into the abdominal cavity and moves the abdomen outward to create a _____ pressure inside the chest. A. Positive B. Negative C. Neutral
B. Negative (RATIONALE: The process of respiration/gas exchange begins with the act of inspiration which is initiated by the contraction of the diaphragm. The negative pressure facilitates the inward flow of air to the lungs because gases flow from higher (atmospheric pressure) to lower pressure. Reference Berne & Levy Physiology 6th ed. Chap. 20 p. 425)
34
Which of the following muscles of inspiration causes an increase in both the lateral and AP diameter of the thorax? A. External Intercostal Muscle B. Internal Intercostal Muscle C. Sternocelidomastoid D. Transversus Abdominis
A. External Intercostal Muscle (RATIONALE: The external intercostal Muscle pulls the ribs upward and forward which facilitates an increase in the lateral and AP diameter of the lungs. Reference Berne & Levy Physiology 6th ed. Chap. 20 p. 425)
35
TRUE OR FALSE. Accessory msucles of inspiration do not contract during normal breathing.
TRUE. (RATIONALE. Accessory muslces action during normal breathing is involuntary which does not require contraction. However, they do contract vigorously during exersie, and when airway obstruction is significant, they actively pull up on the rib cage. Reference Berne & Levy Physiology 6th ed. Chap. 20 p. 425)
36
The respiratory muslces' force of contraction ________ when they are stretched and_______ when shortened. A. Increases; Decreases B. Increases; Increases C. Decreases; Decreases D. Decreases: Increases
A. Increases; Decreases (RATIONALE: Respiratory muscles provide the driving force for ventilation and its force of contraction also increases at larger lung volumes. Reference Berne & Levy Physiology 6th ed. Chap. 20 p. 425)
37
The diaphragm can generate airway pressures of up to _____ to _____ cm H2O during maximal inspiratory effort. A. 200 to 300 B. 150 to 300 C. 200 to 250 D. 150 to 200
D. 150 to 200 (Reference Berne & Levy Physiology 6th ed. Chap. 20 p. 425)
38
Lung volume _____ at inspiration and ____ at expiration. A. Increases; Decreases B. Increases; Increases C. Decreases; Decreases D. Decreases: Increases
A. Increases; Decreases (RATIONALE: During inspiration O2 is taken into the lungs thus increasing lung volume, while at exhalation CO2 and other gases flow passively out of the lungs. Reference Berne & Levy Physiology 6th ed. Chap. 20 p. 425)
39
Which of the following is correct? A. Normal Inspiration: Passive Process B. Force Inspiration: Internal Intercostal C. Normal Inspiration: Active Process D. Force Expiration: External Intercostal
C. Normal Inspiration: Active Process (Force Inspiration - External Intercostal; Force Expiration - Internal Intercostal; Normal Expiration - Passive Process)
40
Which of the following statement is/are TRUE? A. The tidal volume is the volume of air remaining in the lungs after the most forceful expiration B. The tidal volume is the volume of air inspired or expired with each normal breath C. The tidal volume is the volume of air (about 3500 milliliters) a person can breathe in, beginning at the normal expiratory level and distending the lungs to the maximum amount D. The tidal volume is the volume of air inspired and expired with each normal breath
Answer: B (A – residual volume; C - inspiratory capacity ( changed “capacity” to “volume”); D – inspired OR expired – not “and”
41
The rate at which new air reaches alveoli is called? A. alveolar ventilation B. The minute respiratory volume C. Alveolar sac ventilation D. Alveoli pressure
A. Alveolar ventilation
42
The lung has two circulations, which of the following statement is/are TRUE? A. a high-pressure, low-flow circulation B. a low-pressure, high-flow circulation C. Neither of A and B D. Both A and B
D. Both A and B
43
TRUE or FALSE. the pleural space—the space between the parietal and visceral pleurae—is called a potential space
Answer: true, it normally is so narrow that it is not obviously a physical space.
44
When the concentration of O2 in the air of the alveoli ________ below normal, especially when it falls below 70 percent of normal (i.e., below 73 mm Hg Po2), the adjacent blood vessels _________, with vascular resistance increasing more than fivefold at extremely low O2 levels? A. decreases; constrict B. decreases; dilate C. increases; dilate D. increases; constrict
A. decreases; constrict
45
which of the following is not part of upper airways? A. Nose B. Trachea C. Sinuses D. larynx
B. Trachea (part of lower airway)
46
Which of the following is TRUE regarding cough and sneeze reflex? A. It removes irritating substances in airway B. It is a protective mechanism C. Both A and B D. None of the above
C. Both A and B
47
What type of pneumocyte that is responsible for gas exchange? A. Type I B. Type II C. Type III D. Type IV
A. Type I
48
Pulmonary circulation carries ____________ blood to the lungs ; bronchial circulation carries ____________ blood to the lungs? A. Oxygenated, Deoxygenated B. Deoxygenated, Deoxygenated C. Oxygenated, Oxygenated D. Deoxygenated, Oxygenated
D. Deoxygenated, Oxygenated
49
Which of the following statements is/are TRUE? A. Restrictive disease is characterized by limitation of airflow usually resulting from an increase in resistance caused by partial or complete obstruction at any level B.Restrictive disease, characterized by reduced expansion of lung parenchyma accompanied by decreased total lung capacity C. In diffuse obstructive diseases, FVC is reduced and the expiratory flow rate is normal or reduced proportionately. Hence, the ratio of FEV1 to FVC is near normal D. Both B and C are correct
"Answer: B
A – Obstructive
C - Restrictive
Source: Robbinson Basic Pathology 8th edition"
50
The major diffuse obstructive disorders are: A. Chronic bronchitis B. Bronchiectasis C. Asthma D. All of the above
"Answer: D
| Source: Robbinson Basic Pathology 8th edition"
51
"Which of the following statements is/are TRUE: A. The total lung capacity is the maximum volume to which the lungs can be expanded with the greatest possible effort. It is equal to the tidal volume plus the residual volume B. Total capacity is equal to about 5,800 mL C. The inspirational capacity equals the inspiratory reserve volume plus the tidal volume plus the expiratory reserve volume D. Both A and B are correct
"
"Answer: B
A – It is equal to the vital volume plus the residual volume
C – Vital capacity
Source: Guyton and Hall: Textbook of Medical Physiology, 12 edition "
52
"What is the marker of lung function? A. Functional Residual Capacity B. Equilibrium Volume C. Vital Capacity D.Either A or B
"
"Answer: D
| Source: Notes from the discussion"
53
"Which of the following statements is/are TRUE: A. Surfactant is an active surface agent in water, which means it greatly increases the surface tension of water B. One of the components of surfactant is dipalmitoyl phosphaditylcholine also known as lysine C. Surfactant is secreted by the type II alveolar epithelial cells D. Both A and C are correct E. Both B and C are correct
"
"Answer: C
A – reduces/decreases
B - Lecithin
Source: Guyton and Hall: Textbook of Medical Physiology, 13 edition"
54
"What is the normal dead space in young adult man?A. 250 mL B. 350 mLC. 500 mL D. 150 mL
"
"Answer: D
Source: Guyton 13th ed. Page 504
"
55
"The total amount of new air moved into the respiratory passages each minute is known as: A. Tidal volume B. Inspiratory reserved volume C. Minute Respiratory Volume D. Residual Volume
"
"Answer: C
Source: Guyton 13th ed. Page 503
"
56
During hypoxia, which of the following statements is/are TRUE: A. All pulmonary arterioles vasodilate B. All arterioles vasodilate C. All pulmonary arterioles vasoconstrict D. All arterioles vasoconstrict
Answer: A
57
Which of the following is/are NOT true regarding pleural pressure and its changes during respiration A. It is slightly negative pressure B. The pressure of the fluid in the thin space between the lung pleura and the chest wall pleura C. During normal expiration ,expansion of the chest cage pulls outward on the lungs with greater force and create a more negative pressure. D. All are true
"Answer: C
C – during inspiration
"
58
Which is not TRUE of the following statements A. Lung compliance is the complete reverse of recoil B. Lung compliance is defined as the extent to which the lungs expand to each unit increase in transpulmonary pressure C. Both are true D. Both are not correct
"
Answer: C
Source: Guyton 13th edition page 499 and lecture note"
59
If the radius of the alveoli increases, what would be the effect: A. Pressure will increase B. Surface tension increases C. NO effect on Pressure and Tension D. Pressure will decrease
"Answer: D
Source: Guyton 13th ed. Page 504
"
60
The volume of air that remains in the lungs at the end of each normal expiration. A. Tidal volume B. residual volume C. functional residual capacity D. functional residual volume
C. Functional Residual Capacity (Guyton page 470)
61
The maximum extra volume of air that can be expired by forceful expiration after the end of a normal tidal expiration; this normally amounts to about 1100 milliliters. A.Expiratory reserve volume B. Residual Volume C. Tidal Volume D. Expiratory Reserve function
B. Residual Volume (Guyton page 469)
62
What is the VA of a normal 67kg person with a respiratory rate of 13 bpm? A. 4200 B. 4360 C. 4550 D. 4530
C. 4550 (Formula VA=RRx(TV-Physiologic dead space) (VA=13bpm(500ml-150) (VA=13bpm(350)) (VA=4550)
63
All but one are structures that comprises the “dead space air”: A. Pharynx B. Nose C. Alveolar sac D. Trachea
C. Alveolar Sac (pharynx, nose, and trachea are the anatomic dead space)
64
This drug is an antidote of acetylcholine, it relaxes the passages enough to relieve obstruction when parasympathetic nervous stimulation occurs in asthma? A.H2 blockers B. Atropine C. ARB D. Norepinephrine
B. Atropine (Guyton page 473)
65
Several substances formed in the lungs are often quite active in causing bronchiolar constriction. Two of the most important of these are: A. Histidine and fast reactive substance of anaphylaxis B. histamine and fast reactive substance of anaphylaxis C. Histamine and slow reactive substance of anaphylaxis D. histidine and slow reactive substance of anaphylaxis
C. Histamine and slow reactive substance of anaphylaxis (Guyton page 473)
66
It applies to the nasal passageways instead of the lower respiratory passages. A. Cough reflex B. Hiccups C. Sneeze reflex D. Coryza
C. Sneeze Reflex (Guyton page 473)
67
Total amount of new air moved into the respiratory passages each minute? A. Minute Respiratory Capacity B. Minute Respiratory movement C. Minute Respiratory Volume D. Minute Respiratory spirometry
C. Minute Respiratory Volume (Guyton page 471)
68
What is the total minute respiratory volume of an adult person with RR of 12bpm? A. 7L/min B 8L/min C. 5L/min D. 6L/min
D. 6L/min (TMR is TVxRR/min) (TMR=TV500ml or .5L x 12bpm) (6L/min)
69
What’s the difference in Lung Volumes and Capacities bet. Males and females? A. 15-20% B. 20-25% C. 25-30% D. 30-35%
B. 20-25% (Guyton page 469)
70
Left in lungs after maximal expiration? A. Residual volume B. Tidal Volume C. Inspiratory Reserve Volume D. Expiratory Reserve Volume
A. Residual Volume (Guyton page 469)
71
The amount of air that remains in the lungs at the end of normal expiration? A. total lung capacity B. Functional residual capcity C. Expiratory reserve volume D. inspiratory reserve volume
C. Expiratory Reserve Volume (Guyton page 469)
72
All but one are resonators. A. mouth B. Nose C. Associated Nasal Sinuses D. Diaphragm
D. Diaphragm (Guyton page 475)
73
Decrease in oxygen affinity of hemoglobin when ph of the blood falls is called: A. Bohr effect B. Ficks law C. Henry's law D. Daltons law of partial pressure
A. Bohr effect
74
An increase in the concentration of 2,3-DPG cause: A. Shift to the right B. Shift to the left C. Increase binding of oxygen D. Decrease unloading of oxygen to the tissues
A. Shift to the right
75
" Increased oxygen causes unloading of carbon dioxide from hemoglobin is called: A. Bohr effect B. Haldane effect C. Ficks law D. Henry’s law
"
B. Haldane effect
76
An increase of pH would cause: A.shift to the right, unloading B. shift to the left, unloading C. shift to the right,binding D. shift to the left, binding
D. Shift to the left, Binding
77
Carbon dioxide is produced in the? A. citric acid cycle B. electron transport C. urea cycle D. pentose phosphate pathway
A. citric acid cycle
78
Primary transport system of carbon dioxide in the blood. A. freely dissolved in the plasma B. carbaminohemoglobin C.HCO3- D. carboxyhemoglobin
C. HCO3-
79
How may ml of new air is brought to the alveoli? A. 500ml B.350ml C. 1L D.2300ml
B. 350ml
80
Site of highest ventilation and perfusion ratio? A.base B. apex C. base and apex D.alveoli
B.. apex
81
Ability of the respiratory membrane to exchange gas between the alveoli and pulmonary blood A. Diffusing capacity B. Diffusion coefficient C. Ficks law of gas diffusion D. Henry's law
A. Diffusing capacity
82
What is the normal repiratory rate of a well person? A. 10 bpm B. 12 bpm C. 16 bpm D. 20 bpm
B. 12 bpm Source: Guyton p.471
83
After a forceful expiration, how much volume of air is left in the lungs? A. 1 L B. 1.2 L C. 1.5 L D. 1.8 L
B.1.2 L Source: Guyton p. 469
84
During exercise, how much does the energy required for respiration increase? A. 20 fold B. 30 fold C. 40 fold D. 50 fold
D. 50 fold Source: Guyton p. 468
85
Which type of cells produce surfactant? A. Pneumocyte type 1 B. Pneumocyte type 2
B. Pneumocyte type 2 Guyton p. 468
86
What is the relation of the surface tension to the radius of the alveolus? A. Directly Proportional B. Inversely Proportional
B. Inversely Proportional Source: Guyton p. 468
87
As a person ages, the normal dead space air value of 150 mL increases or decreases? A. Increases B. Decreases C. Does not change
A. Increases Source: Guyton p 471
88
Which is not included in the computation of the Vital Capacity? A. IRV B. TLC C. VT. D. ERV
B. TLC Source: Guyton p. 469
89
Which of the following is not a fraction of the work of inspiration? A. Elastic work B. Tissue resistance work C. Airway resistance work D. Ventilatory Work
D. Ventilatory Work Source: Guyton p. 468
90
Elastic forces of the lungs are determined by? A. Elastin B. Collagen Fibers C. Both A and C D. None of the above
C. Both A and C Source: Guyton p. 467
91
Which of the following muscles does not help in elevating the rib cage? A. SCM B. Serratus Anterior C. Internal Intercostal D. External Intercostals
D. Internal Intercostals Source: Guyton p 465
92
Which among the following is not a component of surfactant? A. dipalmitoylphosphatidylcholine B. Apoproteins C. Sodium ions D. Calcium ions
C. Sodium Ions Source: Guyton p. 468
93
This is TRUE when the glottis is open and no air is flowing into or out of the lungs: A. The pressures in all parts of the respiratory tree are equal to atmospheric pressure B. The pressure in all parts of the respiratory tree is greater than atmoshpheric pressure C. The pressure in all parts of the respiratory tree is less than atmospheric pressure D. The pressure in all parts of the respiratory tree is slightly less thn atmospheric pressure
A. The pressures in all parts of the respiratory tree are equal to atmospheric pressure
94
The extent to which the lungs will expand for each unit increase in transpulmonary pressure: A. Pleural Pressure B. Lung Compliance C. IRV D. ERV
B. Lung Compliance
95
The following are the most important components of surfactant EXCEPT: A. dipalmitoylphosphatidylcholine(DPPC) B. Apoproteins C. Calcium D. Sodium
D. Sodium
96
The volume of air inspired or expired with each normal breath. A. Tidal Volume B. IRV C. Residual Volume D. Expiratory Reserve Volume
A. Tidal Volume
97
Which of the following is TRUE? A. Inspiratory capacity =ERV + IRV B. Inspiratory capacity = IRV + RV C. Inspiratory capacity = ERV + RV D. Inspiratory capacity = TV + IRV
D. Inspiratory capacity = TV+IRV
98
The maximum amount of air a person can expel from the lungs after first filling the lungs to their maximum extent and then expiring to the maximum extemt can be measured by: A. IRV+TLC B. IRV+TV C. IRV+IC D. IRVxERV
B. IRV + TV
99
This greatly reduces the surface tension of water. A. Spirometer B. Surfactant C. IRV D. Alveolar Radius
B. Surfactant
100
Which of the following is TRUE? A. The smaller the alveolus, the smaller the alveolar pressure B. The greater the alveolus, the greater the alveolar pressure C. The smaller the alveolus, the greater the alveolar pressure D. The alveolar radius is equal to alveolar pressure
C. The smaller the alveolus, the greater the alveolar pressure
101
During strenuous exercise the diffusing capacity for O2 increases. This due to the ff. Except A. Opening of dormant pulmonary capillaries B. Constriction of open capillaries C. Better Va/Q match D. No answer
B. Constriction of open capillaries (Source: Guyton Ch. 39 p. 921)
102
Which of the following statements about the alveolar PCO2 is true A. PCO2 increases directly in proportion to alveolar ventilation B. Alveolar PCO2 increases in inverse proportion to alveolar ventilation C. Both statements are true D. No Answer
A. PCO2 increases directly in proportion to alveolar ventilation (Source: Guyton Ch. 39 p. 916)
103
The O2 concentration of alveoli as well as PaO2 partial pressure is controlled by A. Rate of absorption of O2 in blood B. Rate of entry of new O2 into the lungs by ventilation process C. Both D. No answer
C. Both (Source: Guyton Ch. 39 p. 915)
104
Which statements about the diffusion of gases through tissues is incorrect A. Gases that are of respiratory importance are all highly soluble in lipids B. Major limitation of movement of gases in tissues is the rate at which gases can diffuse through cell membrane C. The diffusion of gases through tissues, including respiratory membrane is equal to diffusion of these gases in water D. No Answer
B. Major limitation of movement of gases in tissues is the rate at which gases can diffuse through cell membrane (Source: Guyton Ch. 39 p. 912)
105
At this zone of the lung, blood flow is lowest and alveolar pressure >/= arterial pressure > venous pressure. A. Zone 3 B. Zone 2 C. Zone 1 D. Zone 4
Answer: c) zone 1 Source: Constanzo, Linda S. .(2014). Physiology (5th ed.), p. 220. Philadelphia, PA: Elsevier
106
It is the measure of the net tendency of the gas molecules to move through the membrane: A. diffusion coefficientg B. thickness of the membrane C. surface are of the membrane D. Pressure difference across the respiratory membrane
D. Pressure difference across the respiratory membrane Rationale: It is the difference between partial pressure of the gas in the alveoli and the partial pressure of the gas in the pulmonary capillary blood since the partial preassure represents a measure of the total number of molecules of a particular gas striking a unit area of the alveolar surface of the membrane in unit time, and the pressure of the gas in the blood represents the number of molecules that attempt to escape from the blood in the opposite direction.
107
Respiratory physiology deals with mixtures of gases, mainly oxygen, nitrogen, and carbon dioxide. The rate of diffusion of each of these gases is directly proportional to the pressure caused by that gas alone, which is called __________ : A. Net diffusion B. Partial Pressure C. Solubility coefficient D. vapor pressure
B. Partial pressure (source: Guyton Ch 39 p.909)
108
The slow replacement of the alevolar air is important because of the following EXCEPT: A. It prevents abrupt changes in gas concentrations of the blood. B. It helps excessive increase and decreases in tissue oxygenation C. It makes the respiratory control mechanism more stable. D. It causes an excessive increase in tissue pH
D. It causes an excessive increase in tissue pH (source: Guyton Ch 39 p.915)
109
The following are factors that determine how rapidly a gas will pas through the membrane EXCEPT: A. thickness of the membrane B. partial pressure difference of the gas between the two sides of the membrane C. Diffusion coefficient D. Tension area of the membrane
D. Tension area of the membrane Rationale: It should be the surface area of the membrane
110
What is the AVERAGE diffusing capacity for oxygen under resting conditions? A. 23ml/min/mm Hg B. 30ml/min/mm Hg C. 15ml/min/mm Hg D. 21mm/min/mm Hg
D. 21mm/min/mm Hg (Source: Guyton Ch 39 p.921)
111
The greater the physiologic shunt, the ______ amount of blood that fails to be oxygenated as it passes through the lungs: A. greater B.lesser C. No effect D. equal
A. Greater (Source: Guyton Ch 39 p.925)
112
In the upright position, both pulmonary capillary blood flow and alveolar ventilation of a normal person are : A. Greater in the upper part of the lung than in the lower part B. Less in the upper part of the lung than in the lower part C. Less in the lower part of the lung than in the upper part D. Greater in the lower part of the lung than in the upper part.
B. Less in the upper part of the lung than in the lower part (Source: Guyton Ch 39 p. 926)
113
In chronic obstructive lung disease, some areas of the lung exhibit: A. serious physiologic shunt B. serious physiologic dead space C. Both A and B D. none of the above
C. Both A and B (Source: Guyton Ch 39 p.926)
114
The total quantitative amount of shunted blood per minute is called : A. physiologic shunt B. Physiologic dead space C. Diffusion coefficient D. ventilation-perfusion ratio
A. Physiologic Shunt (Source: Guyton Ch 39 p. 925)
115
It is defined as the volume of gas that will diffuse through the membrane each minute for a partial pressure difference of 1 mm Hg: A. Respiratory membrane Diffusing capacity B. Doxygen Diffusing Capacity C. FRC D. Diffusion coefficient
A. Respiratory Membrane Diffusing Capacity (Source: Guyton Ch 39 p.921)
116
Which of the following factors does NOT affect diffusion in respiratory membrane? A. Membrane thickness B. Pressure difference C. Gas concentration D. Membrane surface area
C. Gas concentration (Guyton Ch39 p.1236
117
As stated by the Fick's Law of gas diffusion, diffusion rate is inversely proportional to which of the following: A. Solubilty B. Molecular weight C. Cross-sectional area D. Diffusion coefficient
B. Molecular weight(Guyton Ch9. p1238)
118
In Emphysema, many of the alveoli coalesce, with dissolution of many alveolar walls. What would be the effect of this in the rate of gas diffusion in the respiratory membrane? A. Increase B. Decrease C. No change
B. Decrease (Guyton Ch39 p1236)
119
Niel, a 21 years old athlete is resting from a work out, what do you think is the diffusing capacity for oxygen in the respiratory membrane? A. 21ml/min/mmHg B. 12ml/min/mmHg C. 60ml/min/mmHg D. 56ml/min/mmHg
A. 21ml/min/mmHg (Guyton Ch9. p1238)
120
Which area has the highest Ventilation-Perfusion ratio? A. Base B. Apex C. Left Lung D. Right Lung
B. Apex
121
What states the significance of the Ventilation-Perfusion ratio? A. Different areas of the lung have dfferent perfusion and ventilation B. Different areas of the lungs vary in membrane thickness C.Parts of the lungs have different partial pressures
A.Different areas of the lung have dfferent perfusion and ventilation (Guyton Ch39. p1241)
122
Which of the following is higher at the apex of the lung than at the base when a person is standing? A. V/Q ratio B. Blood Flow C. Ventilation D. Lung Compliance
A. V/Q ratio (Guyton Ch9. p1244)
123
People who are chain smoker develop various degrees of bronchial obstruction, what would be the effect of this in their VA/Q? A. Increase B. Decrease C. No Change
B. Decrease (Guyton Ch9. p1244)
124
The relationship of Partial pressure with the concentration of dissolved gas and solubility coefficient is expressed by, A. Dalton's Law B. Henry's Law C. Fick's Law D. Frank-Starling's Law
B. Henry's Law (Guyton Ch9. p1220)
125
In accordance to the Diffusion Coefficient of gas (Diffusion Coefficient=S/√MW), which of the following is TRUE. A. O2 > CO2 >N2 B. N2 > O2 >CO2 C. CO2 > O2 > N2 D. O2
C. CO2 > O2 > N2 (Guyton Ch9. p1237)
126
Which of the following will cause an decrease in Diffusion Rate? A. Increase in Partial difference B. Increase in Diffusion Coefficient C. Increase in Distance of diffusion D. Decrease in Distance of Diffusion
C. Increase in Distance of diffusion (Basis: Fick's Law)
127
The volume of Inhaled new air that is brought to the alveoli. A. 450ml B. 350ml C. 230ml D. 400ml
B. 350ml (Handout)
128
Defined as the volume of gas that will diffuse through the membrane each minute for a pressure difference of 1mmHg. A. Diffusing Capacity B. Solubility Coefficient C. Diffusion Coefficient D. Diffusion Rate
A. Diffusing Capacity (Handout)
129
Due to exercise, cardiac output will increase and the time that the blood remains in the pulmonary capillary may be reduced to less than ________ the normal amount. A. 1/8 B. 1/4 C. 1/2 D. 1/3
C. 1/2 ( Guyton p. 527)
130
Under normal conditions, _________ of oxygen from the lungs is carried to the tissues of the body in combination with hemoglobin. The remaining _______ is dissolved in water of plasma and blood. A. 97%, 3% B. 80%, 20% C. 95%, 5% D. 75%, 25%
A. 97%, 3% (Guyton p. 530)
131
What is the required O2 pressure for intracellular metabolism? A. 0.5 mmHg B. 1mmHg C. 2 mmHg D. 4 mmHg
B. 1 mmHg (Guyton p. 533)
132
The dissolved CO2 in the blood reacts with water to form ________. A. Carbaminoic acid B. Carbon acid C. Cardonic acid D. Cabonic acid
D. Carbonic acid (Guyton p. 535)
133
The ratio of CO2 output to O2 uptake is called ______. A. Pulmonary exchange ratio B. Respiratory output ratio C. Pulmonary output ratio D. Respiratory exchange ratio
D. Respiratory exchange ratio (Guyton p. 536)
134
During strenuous exercise, a person’s body may require as much as how many times the normal amount of oxygen? A. 10 times b. 20 times c. 30 times d.40 times
B.20 times. (Guyton page 495)
135
Type of blood flow wherein the blood is shunted past the gas exchange. A.“Gas shunt” B. “Blood shunt” C.“Shunt flow” D. “gas exchange shunt flow”
C. “Shunt flow” (Guyton page 496)
136
Under normal conditions, oxygen is carried to the tissues almost entirely by? A. Myoglobin B.Hemoglobin C.Carbaminohemolobin D. Apoferritin
B. Hemoglobin (Guyton p. 498)
137
It illustrates the dependence of total blood carbon dioxide in all its forms on PCO2. A. Carbon Dioxide Dissociation curve B.Oxygen Dissociation Curve C.Hydrogen Dissociation Curve D.Carbaminohemoglobin Dissociation Curve
A. Carbon Dioxide Dissociation Curve (Guyton p. 511)
138
Compared with systemic arterial blood, pulmonary arterial blood has a higher? A.Oxygen content B.pH C.bicarbonate ion concentration D.Hemoglobin concentration
C. Bicarbonate Ion Concentration (Guyton p. 503)
139
Most oxygen transported in the blood is transported as? A.Gas dissolved in plasma B. Oxyhemoglobin C. Carboxyhemoglobin D.Bicarbonate
B. Oxyhemoglobin (Guyton p. 503)
140
A right shift of the oxygen-hemoglobin dissociation curve in response to high blood CO2 releases O2 from the blood in the tissues. This is called: A. Wenders effect B. Hydenvall effect C. Positive effect D. Bohr effect
D. Bohr Effect (Guyton p. 532)
141
A phenomenon called chloride shift states that chloride content of ________ RBC is greater than that of ________ RBC. A. Pulmonary, cardiac B. Venous, arterial C. Arterial, venous D. Cardiac, pulmonary
B. Venous, arterial (Guyton p. 535)
142
Haldane Effect A. Doubles the pickup of carbon dioxide in the tissues B.Triples the pickup of carbon dioxide in the tissues C.Triples the pickup of oxygen in the lungs D.Doubles the pickup of oxygen in the lungs
A. Doubles the pickup of carbon dioxide in the tissues (Guyton p. 503)
143
The carbonic acid formed when ______ enters the blood decreases blood pH. A. CO2 B. HCO3- C. H+ D. H2CO3
A. CO2 (Guyton p. 536)
144
Increase in blood pH will shift the O2-Hg dissociation curve to the _______. A. Left B. Right C. Normal level D. No change
A. left (Guyton p. 532)
145
When oxygen is metabolized in the cells, carbon dioxide may be formed that causes? A. Increase extracellular carbon dioxide pressure B. Increase intracellular carbon dioxide pressure C. Decrease intracellular carbon dioxide pressure D. Decrease extracellular carbon dioxide pressure
B. Increase intracellular carbon dioxide pressure (Guyton p. 495)
146
How long will the blood remains in the pulmonary capillary during an increased cardiac output when exercising? A.Reduced to less than one-half normal B.Reduced to less than one-fourth normal C.Reduced to less than one-third normal D.Reduced to less than two-third normal
A. Reduced to less than one-half normal (Guyton page 495)
147
The percentage of the blood that gives up its oxygen as it passes through the tissue capillaries is called? A. utilization coefficient B. capacity coefficient C.oxygen affinity coefficient D.none of the above
A. Utilization coefficient (Guyton p. 499)
148
What will cause the shift of oxygen- hemoglobin dissociation curve to the right? A. Decreased BPG B. Increased temperature C.Decreased temperature D.Decreased hydrogen ions
ANS: B. increased hydrogen ions, increased CO2, increased temperature, increased BPG all will cause the oxygen-hemoglobin dissociation curve to the right. Ref: p.500
149
What effect results from the simple fact that the combination of oxygen with hemoglobin in the lungs causes hemoglobin to become a stronger acid? A. Bohr effect B. Carbonic Anhydrase effect C. Buffer effect of hemoglobin D. Haldane effect
D. Haldane effect (Guyton p.503)
150
For gas exchange to be efficient, the respiratory membrane must be ________. A. at least 3 micrometers thick B. 0.5 to 1 micrometer thick C.between 5 and 6 micrometers thick D. The thickness of the respiratory membrane is not important in the efficiency of gas exchange
B. 0.5 to 1 micrometer thick (Guyton p. 502)
151
It causes the fall of Po2 of the blood for about 95 mmHg. A. Capillary admixture of blood B.Arterial admixture of blood C.Venous admixture of blood D. Interstitial fluid
C. Venous admixture of blood (Guyton page 496)
152
What happens when Po2 is low just like in the tissue capillaries? A. Oxygen binds with Hgb B. Oxygen is released from the Hgb C. C02 dissociates in the blood D. C02 and 02 combine together
B Oxygen is release from the Hgb (Guyton p. 497)
153
In tissue oxygen buffer system. A. Hgb stabilizes the carbon dioxide pressure in the blood B. hgb release the c02 pressure in the blood C. hgb stabilizes the O2 pressure in the blood D. Hgb releases the O2 pressure in the blood
C. Hgb stabilizes the O2 pressure in the blood (Guyton p. 498)
154
Why do you need to administer pure oxygen to the patient severyly poisoned with CO? A. Oxygen at high alveolar pressure can displace carbon monoxide rapidly from combining with hemoglobin B. Oxygen at low alveolar pressure can displace carbon monoxide rapidly from combining with hemoglobin C. Oxygen at high alveolar pressure can displace carbon monoxide slowly from combining with hemoglobin D. Oxygen at low alveolar pressure can displace carbon monoxide slowly from combining with hemoglobin
A. Oxygen at high alveolar pressure can displace carbon monoxide rapidly from combining with hemoglobin (Guyton p. 501)
155
Carbonic anhydrase A. Catalyzes the reaction between carbon dioxide and oxygen B. Catalyzes the reaction between carbon dioxide and water C. Catalyzes the reaction between nitrogen and oxygen D. Catalyzes the reaction between water and oxygen
B. Catalyzes the reaction between carbon dioxide and water (Guyton p502)
156
Chloride shift: A. Venous RBC > Arterial red cells B. Venous RBC
A. Venous RBC > Arterial red cells (Guyton p502)
157
Tissue Po2 is determined by a balance between what? A. Rate of oxygen transport to the tissues in the blood and the rate at which the oxygen is used by the tissues. B. Rate of carbon dioxide transport to the tissues in the blood and the rate at which oxygen is used by the tissues. C. Rate of carbon dioxide transport to the tissues in the blood and the rate at which carbon dioxide is used by the tissues. D. Rate of oxygen transport to the tissues in the blood and the rate at which carbon dioxide is used by the tissues.
A. Rate of oxygen transport to the tissues in the blood and the rate at which the oxygen is used by the tissues (Guyton p 497)
158
In pulmonary capillaries, oxygen(is) ____ hemoglobin ; in tissue capillaries, oxygen (is)_____ hemoglobin. A. Released from; binds with B. Released from; release from C. Binds with; release from D. Binds with; binds with
C. When Po2 is high, as in pulmonary capillaries, oxygen binds with hemoglobin, but when Po2 is low as in tissue capillaries, oxygen is released from hemoglobin. (Guyton p. 498)
159
Instead of percent saturation of hemoglobin, the oxygen-hemoglobin dissociation curve for the normal person can also be expressed in terms of what? A. Volume percent of oxygen B. Pressure gradient of oxygen C. Volume percent of hemoglobin D. Pressure gradient of hemoglobin
A. volume percent of oxygen (Guyton p498)
160
As blood passes through systemic capillaries, what happens to the affinity of hemoglobin for oxygen and what happens to the Hb-O2dissociation curve? A. Hb affinity for O2 increases and the dissociation curves shifts to the left B. Hb affinity for O2 increases and the dissociation curves shifts to the right C. Hb affinity for O2 decreases and the dissociation curves shifts to the left D.Hb affinity for O2 decreases and the dissociation curves shifts to the right E. neither Hb affinity for O2 nor the Hb-O2 dissociation curve change
D. Hb affinity for 02 decreases and the dissociation curve shifts to the right (Guyton p505)
161
Hemoglobin concentration in systemic venous blood of 20 gm/dl blood is: A. above normal B. Below Normal C. Within Normal Range
A. Above normal (Guyton p503)
162
How many of mL of Oxygen is present in one gram of Hemoglobin? A. 1.35 B. 1.33 C. 1.34 D. 1.36
C. 1.34 (Guyton p498)
163
What is P50?
P02 at which 50% of Hgb is saturated P50 normally at 20mmHg (Guyton p498)
164
TRUE OR FALSE, if the blood flow through a particular tissue is increased 10-fold, the tissue P02 decreases 10-fold
FALSE (Guyton p496)
165
CO2 can diffuse at A. 10 times as rapid as O2 B. 15 times as rapid as O2 C. 20 times as rapid as O2 D. as equal as O2
C. 20 times as rapid as 02 (Guyton p497)
166
What is the relationship between the blood of flow to peripheral tissue PC02? A. Direct B. Indirect C. Equal
B. Indirect (Guyon p497)
167
What is the relationship between tissue metabolic rate to interstitial fluid PCO2? A. Direct B. Indirect C. Equal
A. Direct (Guyton p498)
168
What is the main limiting factor for normal intracellular chemical reactions to occur? A. Oxygen availability B. ADP C. ATP D. all of the above
B.ADP (Guyton p500)
169
"A control center in the brain that mainly causes expiration A. Dorsal respiratory group B. Ventral respiratory group C. Pneumotaxic center D. Apneustic center
"
"B. Ventral respiratory group
(Source: Guyton & Hall Textbook of Medical Physiology 13th Edition p. 539)
"
170
"The neurons of the Dorsal respiratory group can be found in the: A. Nucleus of the Tractus Solitarius B. Nucleus Parabrachialis C. Nucleus Ambiguus D. Nucleus Retroambiguus
"
"A. Nucleus of the Tractus Solitarius
| (Source: Guyton & Hall Textbook of Medical Physiology 13th Edition p. 53)"
171
"The main effect of this center is to control the “switch off” point of the inspiratory ramp consequently controlling the filling phase of the lung cycle A. Dorsal respiratory group B. Ventral respiratory group C. Pneumotaxic center D. Apneustic center
"
"C. Pneumotaxic center
| (Source: Guyton & Hall Textbook of Medical Physiology 13th Edition p. 540)"
172
"The following are true of the Hering-Breuer Reflex EXCEPT A. It is a protective mechanism for preventing excess lung inflation. B. It is not activated until the tidal volume increases to more than 3 times normal. C. Lung inflation signals an increase in inspiration. D. When lungs become inflated, the stretch receptors activate an appropriate feedback that “switches off” the inspiratory ramp.
"
"C. Lung inflation signals an increase in inspiration
| (Source: Guyton & Hall Textbook of Medical Physiology 13th Edition p. 540)"
173
"What is the ultimate goal of respiration? A. Maintain 02 concentration B. Maintain CO2 concentration C. Maintain 02 and CO2 concentrations D. Maintain 02, CO2, and hydrogen concentrations
"
"D. Maintain 02, CO2, and hydrogen concentrations
(Source: Guyton & Hall Textbook of Medical Physiology 13th Edition p. 541)
"
174
"These are special nervous chemical receptors located outside the brain responsible for detecting changes in 02 in the blood. A. Carotid bodies chemoreceptors B. Aortic bodies chemoreceptors C. Respiratory center neurons D. Both A and B
"
"D. Both A and B
(Source: Guyton & Hall Textbook of Medical Physiology 13th Edition p.542)
"
175
"It is an additional neuronal area highly sensitive to changes in blood PCO2 or hydrogen concentration. A. Peripheral chemoreceptors B. Baroreceptors C. Chemosensitive area D. Nucleus parabrachilais
"
"C. Chemosensitive area
| (Source: Guyton & Hall Textbook of Medical Physiology 13th Edition p. 541)"
176
"Why does CO2 have a more dominant effect in stimulating chemosensitive neurons than hydrogen ions? A. CO2 changes hydrogen ion concentration. B. Blood brain barrier is not permeable to hydrogen ions. C. There is more blood CO2 present than hydrogen ions.
D. Sensor neurons are especially excited by CO2.
"
"B. Blood brain barrier is not permeable to hydrogen ions.
| (Source: Guyton & Hall Textbook of Medical Physiology 13th Edition p. 541)"
177
"According to recent studies, during hypoxia, what is the key excitatory neurotransmitter released by carotid body glomus cells? A. Adenosine triphosphate B. Dopamine C. Acetylcholine D. Epinephrine
"
"A. Adenosine triphosphate
| (Source: Guyton & Hall Textbook of Medical Physiology 13th Edition p. 543)"
178
"The following are true of the “J receptors” EXCEPT? A. They are sensory nerve endings in the alveolar walls. B. They are stimulated when pulmonary capillaries are filled with blood. C. They give a person a feeling of dyspnea. D. They respond to changes in oxygen in blood
"
"D. They respond to changes in oxygen in blood.
(Source: Guyton & Hall Textbook of Medical Physiology 13th Edition p. 546)
"
179
"What is the cause of “Obstructive Sleep Apnea”? A. Blockage of upper airway B. Impaired central nervous system respiratory drive C. Neural drive to respiratory muscles is abolished D. Both B and C
"
"A. Blockage of upper airway
| (Source: Guyton & Hall Textbook of Medical Physiology 13th Edition p. 547)"
180
"The neurons of the Pneumotaxic center can be found in the: A. Nucleus of the Tractus Solitarius B. Nucleus Parabrachialis C. Nucleus Ambiguus D. Nucleus Retroambiguus
"
"B. Nucleus Parabrachialis
| (Source: Guyton & Hall Textbook of Medical Physiology 13th Edition p. 540)"
181
"The following are true of Cheyne-Stokes breathing EXCEPT: A. It is a type of periodic breathing B. It is a normal physiologic respiration C. It involves slowly waxing and waning respiration D. It occurs about every 40 to 60 seconds
"
"B. It is a normal physiologic respiration
| (Source: Guyton & Hall Textbook of Medical Physiology 13th Edition p. 547)"
182
"Maximal amount of O2 bound to hemoglobin at 100% saturation (mL O2/hemoglobin) A. O2 Binding Capacity B. O2 content C. Hemoglobin concentration D. Dissolved O2
"
"A. O2 Binding Capacity
| (Source: Contanzo, Physiology 6th edition)"
183
"Hemoglobin combines rapidly and reversibly with O2 to form ________. A. Deoxygemoglobin B. Oxyhemoglobin
"
"B. Oxyhemoglobin
| (Source: Contanzo, Physiology 6th edition)"
184
"The hemoglobin 02 dissociation curve is almost flat when _________. A. PO2 is below 60 and 100 mmHg B. PO2 b comes 40 mmHg C. PO2 IS BETWEEN 60 AND 100mmHg D. PO2 is above 60 and 100 mmHg
"
"C. PO2 IS BETWEEN 60 AND 100mmHg
| (Source: Contanzo, Physiology 6th edition)"
185
"An increase in PCO2, temperature, 2,3DPG is A. Shift to the right B. Shift to the left
"
"A. Shift to the right
| (Source: Contanzo, Physiology 6th edition)"
186
"An increase in pH A. Shift to the left B. Shift to the left
"
"B. Shift to the left
| (Source: Contanzo, Physiology 6th edition)"
187
"Where does this mechanism occur: HCO 3- enters the RBCs in exchange for Cl- . HCO 3- recombines with H+ to form H2CO3, which decomposes into CO2 and H2O. Thus, CO2, originally generated in the tissues is expired. A. Lungs B. Tissues
"
"A. Lungs
| (Source: Contanzo, Physiology 6th edition)"
188
"Decreases the affinity of hemoglobin for O2 and facilitates the delivery of O2 to the tissues during this period of high demand. A. Shift to the right B. Shift to the left
"
"A. Shift to the right
| (Source: Contanzo, Physiology 6th edition) "
189
"During exercise, the tissues produce more CO2, which decreases tissue pH and through the Bohr effect, stimulates O2 delivery to the exercising muscle. A. Shift to the right B. Shift to the left
"
"A. Shift to the right
| (Source: Contanzo, Physiology 6th edition)"
190
The adaptation to chronic hypoxemia includes increased synthesis of 2,3DPG, which binds to hemoglobin and facilitates unloading of O2 in the tissues. A. Shift to the right B. Shift to the left
"A. Shift to the right
| (Source: Contanzo, Physiology 6th edition)"
191
"Most carbon dioxide is transported in blood by: A. The globin portion of Hg B. The heme portion of Hg C. Conversion to bicarbonate ion D. Any plasma protein
"
"C. Conversion to bicarbonate ion
| (Source: Contanzo, Physiology 6th edition)"
192
"During carbon monoxide poisoning, the CO competes for O2-binding sites on hemoglobin. The affinity of hemoglobin for CO is 200 times its affinity for O2. This causes for: A. Shift to the right B. Shift to the left
"
"B. Shift to the left
| (Source: Contanzo, Physiology 6th edition)"
193
"Mr.LotLot was jogging along Luneta. He remembered that during his lectures in school that his alveolar ventilation increases several-fold while he is jogging but could not remember the reason why. Which of the following factors is most likely to cause intense ventilation during strenuous exercise? A. Collateral impulses from higher brain centers B. Increased mean arterial PCO2 C. Decreased mean arterial PO2 D. Decreased mean venous PO2 E. Decreased mean arterial pH
"
"A. Collateral impulses from higher brain centers
(Source: Chapter 41 Regulation of Respiration Page 962 Guyton and Hall, 12th edition. Because strenuous exercise does not change significantly the mean arterial Po2, Pco2, or pH, it is unlikely that these play an important role in stimulating the immense increase in ventilation. Although the mean venous Po2 decreases during exercise, the venous vasculature does not contain chemoreceptors that can sense Po2. The brain, on transmitting motor impulses to the contracting muscles, is believed to transmit collateral impulses to the brain stem to excite the respiratory center. Also, the movement of body parts during exercise is believed to excite joint and muscle proprioceptors that then transmit excitatory impulses to the respiratory center.)"
194
"The basic rhythm of respiration is generated by neurons located in the medulla. Which of the following limits the duration of inspiration and increases respiratory rate? A. Apneustic center B. Dorsal respiratory group C. Nucleus of the tractus solitarius D. Pneumotaxic center E. Ventral respiratory group
"
"D. Pneumotaxic center
(Source: Chapter 41 Regulation of Respiration, Page 951, Guyton and Hall. The pneumotaxic center transmits signals to the dorsal respiratory group that “switch off” inspiratory signals, thus controlling the duration of the filling phase of the lung cycle. This has a secondary effect of increasing the rate of breathing, because limitation of inspiration also shortens expiration and the entire period of respiration.)"
195
"A special set of respiratory neurons that are inactive during normal quiet respiration then becomes active, contributing to the respiratory drive when respiratory drive for increased pulmonary ventilation becomes greater than normal. These neurons are located in which of the following structures? A. Apneustic center B. Dorsal respiratory group C. Nucleus of the tractus solitarius D. Pneumotaxic center E. Ventral respiratory group
"
"E. Ventral respiratory group
(Source: Chapter 41 Regulation of Respiration PAGE 951 GUYTON AND HALL, 12th edition. The basic rhythm of respiration is generated in the dorsal respiratory group of neurons, located almost entirely within the nucleus of the tractus solitarius. When the respiratory drive for increased pulmonary ventilation becomes greater than normal, respiratory signals spill over into the ventral respiratory neurons, causing the ventral respiratory area to contribute to the respiratory drive. However, neurons of the ventral respiratory group remain almost totally inactive during normal quiet breathing.)
"
196
"At a party, a 17-year-old male was hyperventilating. His friend gave him a paper bag over his mouth and lets him breathe in and out of the bag. As he continues to breathe into this bag, his rate of breathing continues to increase. Which of the following is responsible for the increased ventilation? A. Increased alveolar Po2 B. Increased alveolar Pco2 C. Decreased arterial Pco2 D. Increased pH
"
"B. Increased alveolar Pco2
(Rationale: In a normal person the alveolar gases are the same as the arterial blood. With rebreathing, the exhaled CO2 is never removed and continues to accumulate in the bag. This increase in alveolar and thus arterial Pco2 will be the stimulus for the increased breathing. The person hyperventilates in an attempt to get more oxygen. This decreases the carbon dioxide in their blood even more, and exacerbates the problem. The best way to stop it is to shove a barrier between the sufferer and the open air. By forcing them to rebreathe their exhaled carbon dioxide, it's possible to increase carbon dioxide levels in their blood, and deliver more oxygen to tissues. He will have a decrease alveolar Po2, not increased, with the decreased Po2 stimulating breathing. A decreased Pco2 will not stimulate ventilation. An increased pH, alkalosis, will not stimulate ventilation.)
"
197
"In persons with sleep apnea, loud snoring and labored breathing occur soon after falling asleep. The snoring becomes louder and proceeds, is then interrupted by a long silent period during which no breathing occurs. These periods of apnea result in significant decrease and increase of which of the following that would greatly stimulate respiration? A. Decrease in PO2 and Increase in PCO2 B. Increase in PO2 and Decrease in PCO2 C. Increase in PO2 and Increase in PCO2 D. Decrease in PO2 and Decrease in PCO2
"
"A. Decrease in PO2 and Increase in PCO2
| (Source: Page 968, Chapter 41 Regulation of Respiration Guyton.)"
198
"Sleep apnea can be caused by obstruction of which group? A. Mouth, Pharynx, Trachea B. Lower Airways C. Upper airways, Pharynx D. Trachea, Airways, Alveoli
"
"C. Upper airways, Pharynx
| (Source: Page 968, Chapter 41 Regulation of Respiration Guyton.)"
199
"A 56-year-old man inhaled as much air as possible and then expired with a maximum effort until no more air could be expired. This produced the maximum expiratory flow-volume curve. What is the forced vital capacity(FVC) of this man (in liters) If TLC = 5.5 L and RV = 1.0 L.? A. 1.5 B. 2.5L C. 3.5L D. 4.5L E. 5.5L F. 6.5L
"
"D. 4.5L
| (Rationale: FVC = 5.5 − 1.0 = 4.5 L.)"
200
"Oxygen therapy is most beneficial in which of the following situations? Lung function is normal. A. Anemia B. CO2 retention (COPD) C. Cyanide poisoning D. High altitude
"
"D. High altitude
(Source: TMP12 507–509, 517–518, 521. Increasing the inspired Po2 will result in an increase in the dissolved amount of oxygen. High altitude has lower barometric pressure, so less Po2 and supplemental oxygen will help
will help.)
"
