For air to flow into or out of the lungs, there must be
A. a volume gradient established between the atmosphere and the alveoli.
B. a temperature gradient between the atmosphere and the alveoli.
C. a pressure gradient established between the atmosphere and the alveoli.
D. a diffusion gradient between the atmosphere and the alveoli.
E. None of these choices is correct.
(
Question 2) Which of the following factors keeps the alveoli expanded?
A. a pneumothorax
B. negative pleural pressure
C. alveolar pressure being equal to atmospheric pressure
D. a reduction in surfactant
E. negative intra-alveolar pressure
(
Question 3) During expiration, the alveolar pressure must be
A. greater than atmospheric pressure.
B. less than atmospheric pressure.
C. equal to atmospheric pressure.
D. greater than pleural pressure.
E. None of these choices is correct.
(
Question 4) During inspiration, contraction of the diaphragm causes the volume of Mr. Jones' thoracic cavity to increase and the pleural pressure to decrease. The pressure in his alveoli (Palv) will
A. decrease below atmospheric pressure (PB), causing air to move out of his lungs.
B. become greater than atmospheric pressure (PB), causing air to move into his lungs.
C. decrease below atmospheric pressure (PB), causing air to move into his lungs.
D. become greater than atmospheric pressure (PB), causing air to move out of his lungs.
E. does not change.
(
Question 5) Surfactant facilitates alveolar ventilation by
A. decreasing the surface tension between water molecules on the lining of the alveoli.
B. decreasing thoracic compliance.
C. attracting water to the alveolar surface.
D. increasing the surface area for gas exchange.
E. increases the surface tension between fluid and the alveoli.
(
Question 6) Oxygenated blood is carried to the tissues of the lungs via the
A. pulmonary veins.
B. bronchial arteries.
C. pulmonary artery.
D. abdominal aorta.
E. pleural arteries.
(
Question 7) Which of the following statements concerning the lungs and the pleura is true?
A. Each lung is suspended in a separate pleural cavity.
B. Parietal pleura covers the surface of each lung.
C. The space between the visceral and parietal pleurae is called the mediastinum.
D. The pleural fluid assists in gas exchange.
E. The pleural membranes adhere, but cannot slide past each other.
(
Question 8) When the inspiratory muscles contract,
A. thoracic volume increases.
B. pleural pressure increases.
C. the alveolar pressure increases.
D. expiration occurs.
E. thoracic volume decreases.
(
Question 9) Which of the following statements is true?
A. As thoracic volume increases, alveolar pressure (Palv) increases.
B. In expiration, the thoracic volume increases.
C. Constriction of bronchioles assists breathing.
D. As alveolar volume increases, alveolar pressure (Palv) decreases.
E. Pressure is directly proportional to volume.
(
Question 10) The lungs have
A. one blood flow route and one lymphatic supply.
B. two blood flow routes and one lymphatic supply.
C. one blood flow route and two lymphatic supplies.
D. two blood flow routes and two lymphatic supplies.
E. three blood flow routes and one lymphatic supply.
Quick Reply
