MULTIPLE CHOICE 1. The body’s mechanism for conducting air in and out of the lungs is known as which of the following? a. External respiration b. Internal respiration c. Spontaneous ventilation d. Mechanical ventilation ANS: C The conduction of air in and out of the body is known as ventilation. Since the question asks for the body’s mechanism, this would be spontaneous ventilation. External respiration involves the exchange of oxygen (O2) and carbon dioxide (CO2) between the alveoli and the pulmonary capillaries. Internal respiration occurs at the cellular level and involves movement of oxygen from the systemic blood into the cells. DIF: 1 REF: pg. 3 2. Which of the following are involved in external respiration? a. Red blood cells and body cells b. Scalenes and trapezius muscles c. Alveoli and pulmonary capillaries d. External oblique and transverse abdominal muscles ANS: C External respiration involves the exchange of oxygen and carbon dioxide (CO2) between the alveoli and the pulmonary capillaries. Internal respiration occurs at the cellular level and involves movement of oxygen from the systemic blood into the cells. Scalene and trapezius muscles are accessory muscles of inspiration. External oblique and transverse abdominal muscles are accessory muscles of expiration. DIF: 1 REF: pg. 3 3. The graph that shows intrapleural pressure changes during normal spontaneous breathing is depicted by which of the following? a. b. c. d. ANS: B During spontaneous breathing the intrapleural pressure drops from about -5 cm H2O at end-expiration to about -10 cm H2O at end-inspiration. The graph depicted for answer B shows that change from -5 cm H2O to -10 cm H2O. DIF: 1 REF: pg. 4 4. During spontaneous inspiration alveolar pressure (PA) is about: ________________. a. - 1 cm H2O b. + 1 cm H2O c. 0 cm H2O d. 5 cm H2O ANS: A -1 cm H2O is the lowest alveolar pressure will become during normal spontaneous ventilation. During the exhalation of a normal spontaneous breath the alveolar pressure will become +1 cm H2O. DIF: 1 REF: pg. 3 5. The pressure required to maintain alveolar inflation is known as which of the following? a. Transairway pressure (PTA ) b. Transthoracic pressure (PTT) c. Transrespiratory pressure (PTR)