- 1(current)
Q. No.At 40 mm Hg partial pressure of oxygen, the percentage saturation of haemoglobin with oxygen is expected to be about:
1. 50 %
2. 75 %
3. 95 %
4. 99 %
1. 50 %
2. 75 %
3. 95 %
4. 99 %
Subtopic: Â Respiratory System: Exchange of Gases |
 58%
Level 3: 35%-60%
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Consider the two statements:
1. Statement I is correct: Statement II is incorrect
2. Statement I is incorrect: Statement II is correct
3. Statement I is correct: Statement II is correct
4. Statement I is incorrect: Statement II is incorrect
| Statement I: | The respiratory membrane has one layer - the simple squamous epithelium of the alveoli. |
| Statement II: | Oxygen diffuses faster from carbon dioxide across the respiratory membrane. |
2. Statement I is incorrect: Statement II is correct
3. Statement I is correct: Statement II is correct
4. Statement I is incorrect: Statement II is incorrect
Subtopic: Â Respiratory System: Exchange of Gases |
 61%
Level 2: 60%+
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Carbon dioxide partial pressure:
| 1. | increases in the blood as it travels from the systemic venules to the inferior vena cava. |
| 2. | increases in the blood as it travels from the pulmonary arteries to the pulmonary veins. |
| 3. | is greater in the blood in the systemic capillary beds than in the alveoli of the lungs. |
| 4. | is greater in the blood in the systemic capillary beds than in the systemic tissues. |
Subtopic: Â Respiratory System: Exchange of Gases |
 55%
Level 3: 35%-60%
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Regarding the chemical regulation of respiration in humans:
1. Only I and II are correct
2. Only II and III are incorrect
3. I, II and III are incorrect
4. Only I and III are correct
| I: | A chemosensitive area is situated adjacent to the rhythm centre which is highly sensitive to CO2 and hydrogen ions. |
| II: | Receptors associated with aortic arch and carotid artery can recognise changes in O2 concentration and send necessary signals to the rhythm centre for remedial actions. |
| III: | The role of oxygen in the regulation of respiratory rhythm is most significant. |
2. Only II and III are incorrect
3. I, II and III are incorrect
4. Only I and III are correct
Subtopic: Â Respiratory System: Exchange of Gases |Â Respiratory System: Regulation of Respiration |
 61%
Level 2: 60%+
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Consider the two statements:
1. Statement I is correct: Statement II is incorrect
2. Statement I is incorrect: Statement II is correct
3. Statement I is correct: Statement II is correct
4. Statement I is incorrect: Statement II is incorrect
| Statement I: | Carbon dioxide and oxygen compete for binding sites with the hemoglobin. |
| Statement II: | Oxygen dissociates faster from hemoglobin during exercise. |
1. Statement I is correct: Statement II is incorrect
2. Statement I is incorrect: Statement II is correct
3. Statement I is correct: Statement II is correct
4. Statement I is incorrect: Statement II is incorrect
Subtopic: Â Respiratory System: Exchange of Gases |Â Respiratory System: Transport of Gases |
Level 4: Below 35%
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Gas exchange between the blood and tissues occurs:
1. throughout the circulatory system.
2. in the arteries, arterioles and capillaries.
3. in the systemic arteries only.
4. in the capillaries only.
1. throughout the circulatory system.
2. in the arteries, arterioles and capillaries.
3. in the systemic arteries only.
4. in the capillaries only.
Subtopic: Â Respiratory System: Exchange of Gases |
 52%
Level 3: 35%-60%
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Consider the following statements:
| I: | The diffusing capacity of CO2 across the respiratory membrane is higher than that of O2 |
| II: | The presence of Hb increases the efficiency of O2 transport by about 10 times. |
| III: | Carbon monoxide binds to Hb with much more tenacity with respect to O2 |
Which of the above statements are true?
| 1. | I and II only | 2. | I and III only |
| 3. | II and III only | 4. | I, II, and III |
Subtopic: Â Respiratory System: Exchange of Gases |
 53%
Level 3: 35%-60%
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- 1(current)
Q. No.
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