The major function of the lungs is a gas exchange between the lungs and the blood.
Their function in the respiratory system is to extract oxygen from the atmosphere and transfer it into the bloodstream and to release carbon dioxide from the bloodstream into the atmosphere, in a process of gas exchange.
The lower respiratory tract is part of the respiratory system and consists of the trachea and the structures below this including the lungs. The trachea receives air from the pharynx and travels down to a place where it splits (the carina) into a right and left bronchus. These supply air to the right and left lungs, splitting progressively into the secondary and tertiary bronchi for the lobes of the lungs, and into smaller and smaller bronchioles until they become the respiratory bronchioles. These, in turn, supply air through alveolar ducts into the alveoli, where the exchange of gases take place. Oxygen breathed in, diffuses through the walls of the alveoli into the enveloping capillaries and into the circulation, and carbon dioxide diffuses from the blood into the lungs to be breathed out.
Respiratory diseases are a major causes of illness and mortality in Australia. They are highly prevalent in the community and constitute a significant health problem. Each year, chronic respiratory diseases disrupt the daily life and productivity of many individuals and contribute to thousands of deaths.
An estimated 5.8 million Australians had at least one long-term respiratory condition. These chronic respiratory diseases are a diverse group affecting the lungs or respiratory tract for a prolonged period. They are often incurable but are largely manageable. However, for some individuals, their lung disease is so severe that a lung or heart/lung transplant is the only treatment available.
Details for specific lung conditions are available from