Carbon dioxide is transported in blood by all the following mechanisms except:
1. bound to the protein portion of hemoglobin
2. bound to the iron atoms of hemoglobin
3. dissolved in plasma
4. as bicarbonate
The pulmonary function of a person reveals the following values:
a. tidal volume = 500 mL
b. residual volume = 1000 mL
c. inspiratory reserve volume = 2500 mL
d. expiratory reserve volume = 1000 mL
His vital capacity is
1. 3000 mL | 2. 3500 mL |
3. 4000 mL | 4. 5000 mL |
Exchange of gases occurs across the respiratory membrane. Which of the following would increase the rate of diffusion of a gas across the respiratory membrane?
1. | respiratory membrane becomes thicker. |
2. | surface area of the respiratory membrane decreases. |
3. | partial pressure difference of the gas across the respiratory membrane increases. |
4. | diffusion coefficient of the gas decreases. |
When compared with carbon dioxide, the partial pressure of oxygen in the air and its solubility in water is respectively:
1. lower, lower | 2. lower, higher |
3. greater, lower | 4. greater, higher |
Name the cavities in which the lungs are located:
1. pleural and abdominal cavities.
2. pericardial and thoracic cavities.
3. pleural and thoracic cavities.
4. pleural and pericardial cavities.
What is the partial pressure of oxygen and carbon dioxide respectively in the venous blood leaving the tissues [in mm of Hg]?
1. 104, 40 | 2. 95, 40 |
3. 40, 45 | 4. 20, 46 |
A minimal amount of pleural fluid present in the pleural cavity:
1. | provides a medium for the exchange of respiratory gases |
2. | reduces friction between the visceral and parietal pleurae |
3. | provides lubrication for movements of the diaphragm |
4. | permits the exchange of electrolytes during respiration |
When the diaphragm or external intercostal muscles contract, intrapulmonary pressure should
1. | increase | 2. | decrease |
3. | remain constant | 4. | equal atmospheric pressure |
Air conditioning – warming, humidifying and filtering of the air, is the function performed by:
1. | oral cavity | 2. | nasal cavity |
3. | pharynx | 4. | larynx |
During deglutition, the food is prevented from entering into the larynx by the cartilaginous:
1. epiglottis | 2. glottis |
3. aryepiglottic fold | 4. laryngeal prominence |