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The lungs are central to the human respiratory system and the only internal organs that are constantly exposed to the external environment. Tobacco smoke, pollution, infections and genetics are responsible for most lung conditions and diseases.
Conditions and Diseases of the Airways
The trachea is divided at its base into two airways called the bronchi, which lead to each lung. The bronchi split like the branches of a tree into tens of thousands of smaller airways called bronchioles, which connect to tiny air sacs called alveoli.
Asthma is a chronic respiratory disease caused by inflamed and constricted airways. Allergens, such as dust, pollen or tobacco smoke, trigger an attack. A combination of environmental and genetic factors may predispose a person to developing asthma.
Bronchitis is inflammation of the main air passages, which become irritated, swollen and produce mucus. Acute bronchitis generally follows a viral respiratory infection while chronic bronchitis may result from smoking, repeated episodes of acute bronchitis or exposure to occupational or environmental irritants
Chronic obstructive pulmonary disease or COPD refers to a group of lung diseases which cause restriction in the airways. Chronic bronchitis, emphysema and chronic asthmatic bronchitis are the most common COPD conditions. Smoking is the major cause of COPD.
Cystic fibrosis is a genetic, chronic and life-threatening condition causing the abnormal production and accumulation of mucus in the airways of the lungs, in the pancreas, the sweat glands and the male reproductive system.
Conditions and Diseases of the Alveoli
The alveoli are the tiny air sacs where gas exchange, the process of getting oxygen to the red blood cells and eliminating carbon dioxide from the blood happens.
Pneumonia is inflammation of the alveoli caused by bacteria, viruses, fungi or parasites. It can range in seriousness from mild to life-threatening and frequently is a complication of another condition such as the flu.
Emphysema slowly destroys the alveoli and the elastic fibers that hold open the small airways leading to the alveoli.