Residual volume in lungs:
I:  Prevents Lung Collapse
II:  Facilitates Gas Exchange  
1. Only I is correct
2. Only II is correct
3. Both I and II are correct 
4. Both I and II are incorrect 
Subtopic:  Respiratory System: Pulmonary Volumes & Capacities |
Level 3: 35%-60%
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A person exhales forcefully, pushing out all the air he can. If he then breathes in quietly and normally, without making an extra effort, what volume of air will he inhale?
(TV: Tidal Volume; IRV: Inspiratory Reserve Volume; ERV: Expiratory Reserve Volume)
1. TV + IRV 
2. TV only 
3. TV + ERV 
4. TV+IRV+ ERV
Subtopic:  Respiratory System: Pulmonary Volumes & Capacities |
Level 4: Below 35%
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