The respiratory system, also called the pulmonary system, consists of several organs that function as a whole to oxygenate the body through the process of respiration (breathing). This process involves inhaling air and conducting it to the lungs where gas exchange occurs, in which oxygen is extracted from the air, and carbon dioxide expelled from the body. The respiratory tract is divided into two sections at the level of the vocal cords; the upper and lower respiratory tract.
- The upper respiratory tract includes the nasal cavity, paranasal sinuses, pharynx and the portion of the larynx above the vocal cords.
- The lower respiratory tract includes the larynx below the vocal cords, the trachea, bronchi, bronchioles and the lungs.
The lungs are most often considered as part of the lower respiratory tract, but are sometimes described as a separate entity. They contain the respiratory bronchioles, alveolar ducts, alveolar sacs and alveoli.
This article will discuss the anatomy and function of the respiratory system.
| Upper respiratory tract | Nasal cavity, paranasal sinuses, pharynx and larynx above the vocal cords |
| Lower respiratory airways | Larynx below the vocal cords, trachea, bronchi, bronchioles and lungs |
| Functions | Upper respiratory tract: conduction, filtration, humidification and warming of inhaled air Lower respiratory tract: conduction and gas exchange |
