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Q. No.Assertion (A): Thoracic chamber is anatomically an air-tight chamber and any change in its volume has no effect whatsoever on the pulmonary cavity.
Reason (R): Lungs are situated in the thoracic cavity and this arrangement is essential for breathing.
With respect to the above mentioned statements, choose the correct answer from the following options.
1. (A) and (R) are true and (R) is the correct explanation of A
2. (A) and (R) are true but (R) is not the correct explanation of A
3. (A) is true but (R) is false
4. (A) is false but (R) is true
Subtopic: Â Respiratory System: Trachea & Basic Anatomy of Lung |
 79%
Level 2: 60%+
Hints
How many of the given factors affect the exchange of gases between blood and tissues?
Mark the correct option from the following:
| a. | Thickness of diffusion membrane | b. | Solubility of gases |
| c. | Pressure gradient | d. | Concentration gradient |
| 1. | Two | 2. | One |
| 3. | Four | 4. | Zero |
Subtopic: Â Respiratory System: Exchange of Gases |
 79%
Level 2: 60%+
Hints
| Assertion (A): | Emphysema is caused by cigarette smoking. |
| Reason (R): | Cigarette smoking reduces the gaseous exchange area. |
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
| 3. | (A) is True but (R) is False. |
| 4. | Both (A) and (R) are False. |
Subtopic: Â Respiratory Disorders: Part 1 |Â Respiratory Disorders: Part 2 |Â Respiratory Disorders - III |
Level 4: Below 35%
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Assertion (A): Smoking leads to availability of less oxygen to the body.
Reason (R): In presence of CO, O2 binds less with Hb.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Reason (R): In presence of CO, O2 binds less with Hb.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic: Â Respiratory Disorders: Part 1 |Â Respiratory Disorders: Part 2 |Â Respiratory Disorders - III |
 68%
Level 2: 60%+
Hints
Given below are two statements:
| Assertion (A): | At high altitudes, hypoxia may occur. |
| Reason (R): | The percentage of O2 decreases in the air at high altitudes. |
| 1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
| 3. | (A) is true but (R) is false. |
| 4. | Both (A) and (R) are false. |
Subtopic: Â Respiratory System: Exchange of Gases |
 88%
Level 1: 80%+
Hints
Assertion (A): Special vascularised structures called gills are used by most of the aquatic arthropods and molluscs.
Reason (R): Terrestrial arthropods also possess gills.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Reason (R): Terrestrial arthropods also possess gills.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic: Â Respiratory Organs |
 70%
Level 2: 60%+
Hints
| Assertion (A): | Alveoli are the major site of exchange of gases. |
| Reason (R): | CO2 and O2 are exchanged at alveoli by simple diffusion. |
| 1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
| 3. | (A) is true but (R) is false. |
| 4. | Both (A) and (R) are false. |
Subtopic: Â Respiratory System: Trachea & Basic Anatomy of Lung |Â Respiratory System: Exchange of Gases |
Level 3: 35%-60%
Hints
| Assertion(A) | Pneumotaxic centre can moderate the functions of the respiratory rhythm centre. |
| Reason(R) | Neural signal from pneumotaxic centre can reduce the duration of inspiration and thereby alter the respiratory centre. |
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic: Â Respiratory System: Regulation of Respiration |
 83%
Level 1: 80%+
Hints
| Assertion (A): | Hb cannot get saturated with O2 more than 70%. |
| Reason (R): | The affinity O2 to Hb increases with the rise of pCO2. |
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
| 3. | (A) is True but (R) is False. |
| 4. | Both (A) and (R) are False. |
Subtopic: Â Respiratory System: Transport of Gases Part 1 |Â Respiratory System: Transport of Gases Part 2 |Â Respiratory System: Transport of Gases |
 69%
Level 2: 60%+
Hints
Given below are two statements:
| Assertion (A): | Inspiration occurs when intra-pulmonary pressure is lower than atmospheric pressure. |
| Reason (R): | Inspiration is initiated by the relaxation of diaphragm and intercostal muscles. |
| 1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
| 3. | (A) is true but (R) is false. |
| 4. | Both (A) and (R) are false. |
Subtopic: Â Respiratory System: Exchange of Gases |
 86%
Level 1: 80%+
Hints
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