Incidence of emphysema a respiratory disorder is high in cigarette smokers. In such cases

1.  the bronchioles are found damaged
2.  the alveolar walls are found damaged
3.  the plasma membrane is found damaged
4.  the respiratory muscles are found damaged
 

Subtopic:  Respiratory Disorders: Part 1 | Respiratory Disorders: Part 2 |
 91%
From NCERT
Please attempt this question first.
Hints
Please attempt this question first.