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Structure of the Respiratory Tract system
The Respiratory system is composed of two divisions, the Upper Respiratory Tract (URT) and the Lower
Respiratory Tract (LRT).
The URT consists of: the nose, the throat, and the structures associated with them, including the middle ear and the
auditory (Eustachian) tubes. Duct from the sinuses and the nasolacrimal ducts from the lacrimal apparatus empty
into the nasal cavity. The auditory tubes from the middle ear empty into the upper portion of the throat.
apparatus, and middle ear, infections commonly spread from one region to another.
apparatus, and middle ear, infections commonly spread from one region to another.
The LRT consist of the larynx (voice box), trachea (windpipe), bronchial tubes, and alveoli.
Upper Respiratory Tract Infections (URTIs)
Lower Respiratory Tract Infections (LRTIs)
