The lungs are part of the respiratory system, the bodily system that controls breathing and the exchange of air between the body and the environment. According to the Nemours Foundation, people breathe 20,000 times every day, and all of the oxygen used by the body passes through the lungs before heading to other organs via the bloodstream.
Anatomy
The bronchi branch off the trachea to bring air from the windpipe into the lungs. Once inside the lungs, the bronchi branch into smaller bronchi and then into tiny bronchioles. At the end of each bronchiole is an alveolar sac, also called alveoli--the structure that exchanges oxygen from the air with carbon dioxide waste delivered to the lungs by the blood. The diaphragm below the lungs helps the lungs expand and contract to allow breathing to take place, which sends carbon dioxide-rich air out of the lungs and sucks in oxygen-rich air.
Lung Disorders
Several problems can occur in the lungs that cause them to function less efficiently. Asthma is a common condition in which the airways become narrow and breathing becomes difficult. Bronchiolitis occurs when the tiny bronchioles become inflamed, often due to a respiratory virus. Emphysema is a disorder in which the lungs produce too much mucus. Bronchitis occurs when the lining of the bronchial tubes becomes infected and overproduces mucus. Chronic obstructive pulmonary disease is typically caused by air pollutants or cigarette smoke; it's characterized by damaged air sacs in the lungs. The genetic disease cystic fibrosis causes the lungs to produce abnormally thick, sticky mucus.
Infections of the Lungs
Many viruses and bacteria are capable of infecting the respiratory systems, and some of these can move into the lungs. Influenza and the bacteria Streptococcus pneumoniae are both capable of moving into the lungs and causing pneumonia.
Lung Cancer
Lung cancer presents as a tumor, a lump of cells in the lung that shows abnormal growth. This disease develops over a long period and is usually the result of exposure to cigarette smoke or radon, although some people develop it spontaneously.
Care of the Lungs
Care of the lungs involves protecting them from exposure to environmental contaminants that can damage the sensitive bronchioles and alveoli. Cigarette smoke, air pollution and radon can all damage sensitive lung tissues. Avoiding respiratory diseases is another part of lung care. This can involve preventative measures such as hand washing, avoiding sick people and wearing a respiratory mask when in crowded spaces.
