1. Functions of the respiratory tract (from nose to bronchioles) include ___.
A) warming and moistening inhaled air
B) cleaning and humidifying inhaled air
C) detecting odors
D) generating voice
E) all of the above
2. Since cartilage ring is absent in the wall of ____, their caliber decreases significantly during asthma attack.
A) trachea
B) nose
C) bronchi
D) bronchioles
3. Which of the following cells is not a normal component of alveoli (excluding capillaries that surround alveoli) ?
A) type I alveolar cells
B) type II alveolar cells
C) macrophages
D) erythrocytes
4. Which of the cells listed above in question #46 produces surfactant?
5. Dead space in the respiratory system refers to ____.
A) the entire respiratory tract from nose to bronchioles
B) the entire respiratory system from nose to alveoli
6. The structure separating alveolar air and blood in the lungs is called respiratory membrane, including all of the following components EXCEPT ____.
A) the wall of alveoli
B) the wall of the capillary
C) the basement membranes between alveoli and capillary
D) a layer of smooth muscles between alveoli and capillary
7. What happens during inspiration?
A) intrapulmonary pressure decreases
B) intrapulmonary pressure increases
C) atmospheric pressure decreases
D) atmospheric pressure increases
8. Contraction of diaphragm ____.
A) increases intrapulmonary pressure
B) increases vertical dimension of the thoracic cage
C) occurs during expiration
9. Contraction of external intercostal muscles ____.
A) occurs during inspiration
B) occurs during expiration
C) decreases anteroposterior dimension of the thoracic cage
10. Contraction of abdominal muscles ____.
A) decreases pressure inside abdominal cavity
B) is required for inspiration at resting state
C) is involved in forced expiration
11. If the pleural cavity leaks to atmosphere, what will happen?
A) The lungs collapse.
B) The affected lungs cannot expand during inspiration.
C) Both A and B.
12. Which of the following is NOT a property of surface tension?
A) It tends to cause a collapse of the alveoli.
B) It resists against inspiration
C) It resists against expiration
13. Elastic resistance ___.
A) is against inspiration
B) assists inspiration
C) is caused by friction between air flow and respiratory tract
14. Airway resistance ____.
A) is generated by elastic fibers in the lungs
B) increases when airway caliber decreases
C) is against inspiration but not expiration
D) decreases greatly during asthma attack
15. The volume of fresh air inhaled into the lungs during resting inspiration is usually ____.
A) less than 10% of total lung capacity
B) about 40% of total lung capacity
C) about 60% of total lung capacity
D) about 80% of total lung capacity
16. The inspiratory center ____ during inspiration
A) stimulates diaphragm
B) inhibits diaphragm
C) stimulates abdominal muscles
D) inhibits external intercostal muscles
17. The expiratory center _____ during expiration.
A) inhibits inspiratory center
B) stimulates inspiratory center
C) stimulates diaphragm
D) stimulates external intercostal muscles
18. If all nerve fibers connecting medulla oblongata to the rest of whole body are completely severed, respiration will ___.
A) stop
B) continue with smooth rhythm
C) continue but become irregular
19. The primary respiratory centers receive input from ____.
A) limbic system
B) hypothalamus
C) chemoreceptors
D) all of the above
20. Neurons in motor cortex of cerebrum can ____.
A) NOT control respiration at all
B) directly regulate respiration, bypassing the brainstem respiratory centers
C) control respiration voluntarily without limits.
21. Which of the following is the right order of O2 partial pressures from high to low?
A) atmosphere > alveoli > systemic arteries > tissue cells
B) tissue cells > atmosphere > alveoli > systemic arteries
C) alveoli > atmosphere > systemic arteries > tissue cells
D) atmosphere > tissue cells > alveoli > systemic arteries
22. Which of the following factors can affect the efficiency of alveolar gas exchange?
A) concentration gradients of the gases
B) thickness of the respiratory membrane
C) gross area of the respiratory membrane
D) ventilation-perfusion coupling
E) all of the above
23. If erythrocytes are completely removed from the blood, the blood will lose its capacity of transporting oxygen by ___.
A) 5%
B) 25%
C) 50%
D) >95%
24. Association of oxygen with hemoglobin decreases in tissues when ____.
A) tissue oxygen partial pressure increases
B) tissue CO2 partial pressure increases
C) tissue pH increases
D) tissue DPG decreases
KEY
1E 2D 3D 4B 5A 6D 7A 8B 9A 10C
11C 12C 13A 14B 15A 16A 17A 18A 19D 20B
21A 22E 23D 24B