Question: what are the major diseases of the respiratory system?
Answer: Asthma. ... 
Chronic Obstructive Pulmonary Disease (COPD) ... 
Chronic Bronchitis. ... 
Emphysema. ... 
Lung Cancer. ... 
Cystic Fibrosis/Bronchiectasis. ... 
Pneumonia. ... 
Pleural Effusion.