Assertion : Emphysema is a chronic disorder in which alveolar walls are damaged. Reason : Emphysema is closely related to cigarette smoking.

Step-by-step solution

The word "emphysema" means "inflation" or "full of air". Emphysema is an inflation or abnormal distension of the bronchioles or alveolar sacs of the lungs. It causes irreversible distension and loss of elasticity of alveoli. As a result, the alveolar sacs remain filled with air even after expiration. The exhalation becomes more difficult. The lungs remain inflated. Many of the septa between the alveoli are destroyed and much of the elastic tissue of the lungs is replaced by connective tissue. Major causes are cigar