Consider the given two statements:
Assertion (A): Alveoli in the human lungs have a large surface area for efficient gas exchange.
Reason (R): There are about 300 million alveoli in both lungs.
 
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. (A) is False but (R) is True.
Subtopic:  Respiratory System: Upper Respiratory Tract |
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Lungs do not collapse between breaths and some air always remains in the lungs which can never be expelled because?

1. there is a negative pressure in the lungs
2. there is a negative intrapleural pressure pulling at the lung walls
3. there is a positive intrapleural pressure
4. pressure in the lungs is higher than the atmospheric pressure

Subtopic:  Respiratory System: Trachea & Basic Anatomy of Lung |
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Consider the given two statements:
Assertion (A): The thoracic chamber, being airtight, is critical for breathing.
Reason (R):  Movement of rib cage can bring about inhalation and exhalation.
 
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. (A) is False but (R) is True.
Subtopic:  Respiratory System: Trachea & Basic Anatomy of Lung |
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Given below are two statements: 
Assertion (A): The part of the respiratory system starting with the external nostrils upto terminal bronchioles constitutes the conducting part, whereas the alveoli from respiratory part.
Reason (R): Conducting part transports the atmospheric air to alveoli, clears it from foreign particles, humidifies it and also brings the air to body temperature.
 
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:  Respiratory System: Upper Respiratory Tract |
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The heart, trachea, esophagus and associated structures are located in the space between the two lungs called as:
1. mediastinum
2. pleural cavity
3. thoracic cavity
4. parietal cavity
Subtopic:  Respiratory System: Trachea & Basic Anatomy of Lung | Respiratory Organs |
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Consider the two statements:
Statement I: The alveoli have ciliated cells in them to help expel dust particles that make it this far down into the respiratory tract.
Statement II: Gas exchange between the lungs and the blood, and between the blood and tissue fluid, is an active transport process.

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:  Respiratory System: Trachea & Basic Anatomy of Lung |
 54%
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Exhalation of air into the lungs can be brought about by:
I: Contraction of diaphragm
II: Contraction of internal intercostal muscles
III: Contraction of external intercostal muscles
1. Only I and II
2. Only II
3. Only I and III
4. Only III
Subtopic:  Mechanism of Breathing |
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If a person exhales out forcefully by applying all his efforts. What will be the pulmonary volume inhaled by him immediately under normal condition without applying any extra effort? 
1. TV + IRV 
2. TV only 
3. TV + ERV 
4. TV+IRV+ ERV
Subtopic:  Respiratory System: Pulmonary Volumes & Capacities |
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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 %
Subtopic:  Respiratory System: Exchange of Gases |
 55%
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Consider the given two statements: 
Assertion (A): During heavy exercise, hyperventilation occurs to meet the increased oxygen demand. 
Reason (R): Hyperventilation increases the removal of CO2 from the blood, thus maintaining the blood pH. 
 
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. (A) is False but (R) is True.
Subtopic:  Respiratory System: Exchange of Gases |
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