Both carbon dioxide and oxygen move across the respiratory membrane due to:
1. gravity | 2. blood pressure |
3. diffusion | 4. active transport |
With respect to the atmospheric air, the deoxygenated blood flowing into lung capillaries has a higher concentration of:
1. oxygen | 2. both carbon dioxide and oxygen |
3. carbon monoxide | 4. carbon dioxide |
Gas exchange in the human lungs takes place across the respiratory membrane which is made up of:
1. alveolar macrophages and the alveolar cell membrane
2. alveolar cell membrane and its basement membrane
3. alveolar cell membrane and capillary membrane
4. alveolar cell membrane, capillary membrane, and fused basement membranes
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 |
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 |
The partial pressure of oxygen in oxygenated blood is about:
1. 104 mmHg | 2. 100 mmHg |
3. 95 mmHg | 4. 40 mmHg |
During the passage of blood through a tissue with normal metabolism, the percentage of hemoglobin that unloads oxygen is approximately:
1. 10% | 2. 25% |
3. 50% | 4. 75% |
The conversion of carbon dioxide into carbonic acid in the red blood cells is catalyzed by the enzyme:
1. hemoglobin | 2. carbonic anhydrase |
3. carbonic oxidoreductase | 4. carbonic transferase |