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Q. No.Assertion (A): O2 binds with Hb in an irreversible manner.
Reason (R): CO2 combines with Hb both is an irreversible and reversible manner.
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 |Â Respiratory System: Transport of Gases Part 1 |Â Respiratory System: Transport of Gases Part 2 |Â Respiratory System: Transport of Gases |
 74%
Level 2: 60%+
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Assertion (A): The amount of CO2 that can diffuse through the diffusion membrane per unit difference in partial pressure is much higher compared to that of O2.
Reason (R): The solubility of CO2 in blood is 20-25 times higher than that of O2.
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): The solubility of CO2 in blood is 20-25 times higher than that of O2.
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%+
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Assertion (A): In the alveoli, where there is high pO2, low pCO2, lesser H+ concentration and lower temperature, the factors are all favourable for the formation of oxyhemoglobin.
Reason (R): Every 100 mL of oxygenated blood deliver around 2.5 mL of O2 to the tissues normally.
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): Every 100 mL of oxygenated blood deliver around 2.5 mL of O2 to the tissues normally.
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 |
 92%
Level 1: 80%+
Hints
Assertion (A): CO2 is carried by Hb as carbaminohaemoglobin (about 20-25%).
Reason (R): When pCO2, is high and pO2 is low as in tissues, more binding of CO2 to Hb occurs.
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): When pCO2, is high and pO2 is low as in tissues, more binding of CO2 to Hb occurs.
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%+
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Assertion (A): The respiratory rhythm centre, located in the pons region of brain is responsible for regulation of respiration.
Reason (R): Pneumotaxic centre, located in the medulla region of brain moderates the respiratory rhythm 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.
Reason (R): Pneumotaxic centre, located in the medulla region of brain moderates the respiratory rhythm 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 |
 72%
Level 2: 60%+
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Assertion (A): The lungs present in the thoracic chamber is an anatomically air-tight chamber.
Reason (R): The role of oxygen in the regulation fo respiratory rhythm is quite significant.
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): The role of oxygen in the regulation fo respiratory rhythm is quite significant.
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: Regulation of Respiration |
 63%
Level 2: 60%+
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Subtopic: Â Respiratory System: Transport of Gases Part 1 |Â Respiratory System: Transport of Gases Part 2 |Â Respiratory System: Transport of Gases |
 62%
Level 2: 60%+
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Which of the following is not a stimulus for breathing?
1. Arterial pH resulting from CO2 retention
2. Arterial pO2 below 60 mm Hg
3. Rising blood pressure
4. Rising CO2 levels
1. Arterial pH resulting from CO2 retention
2. Arterial pO2 below 60 mm Hg
3. Rising blood pressure
4. Rising CO2 levels
Subtopic: Â Respiratory System: Regulation of Respiration |
 55%
Level 3: 35%-60%
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When we breath in, we inhale many gases, including oxygen. What happens to the gases that the body cannot use?
1. They are absorbed into the digestive system and used to create energy
2. They circulate through the body and are disposed off later
3. They are changed into oxygen by the lungs
4. They are exhaled
1. They are absorbed into the digestive system and used to create energy
2. They circulate through the body and are disposed off later
3. They are changed into oxygen by the lungs
4. They are exhaled
Subtopic: Â Respiratory System: Exchange of Gases |
 68%
Level 2: 60%+
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A large proportion of oxygen is let unused in the human is left unused in the human blood even after its uptake by the body tissues. This O2 :
1. Helps in releasing more O2 to the epithelial tissues
2. Is enough to keep oxyhaemoglobin saturation at 96%
3. Raises pCO2 of blood to 75 mm Hg
4. Acts as a reserve during muscular exercise
1. Helps in releasing more O2 to the epithelial tissues
2. Is enough to keep oxyhaemoglobin saturation at 96%
3. Raises pCO2 of blood to 75 mm Hg
4. Acts as a reserve during muscular exercise
Subtopic: Â Respiratory System: Exchange of Gases |Â Respiratory System: Transport of Gases Part 1 |
 80%
Level 1: 80%+
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