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The upper respiratory system contains the nose, oral cavity, nasal cavity, paranasal sinuses, and the pharynx.
The nose and nasal cavity form the external opening for the respiratory tract. The nasal septum divides the nose into two nostrils.
Inside the nasal cavity, three bony projections known as turbinates increase the nasal mucosa's surface area, aiding in warming and moistening the air upon entry.
Adjacent to the nasal cavity are the paranasal sinuses, which consist of four air-filled cavities: the frontal, ethmoidal, sphenoidal, and maxillary sinuses.
These sinuses are lined with nasal mucosa and ciliated pseudostratified columnar epithelium, contributing to air filtration and humidification.
The pharynx, commonly known as the throat, connects the nasal cavity to the larynx and is subdivided into the nasopharynx, oropharynx, and laryngopharynx.
The nasopharynx is situated posterior to the nose and above the soft palate. The oropharynx lies behind the mouth, including the soft palate, the tonsils, and the back third of the tongue.
The laryngopharynx runs from the hyoid bone to the cricoid cartilage.
The upper respiratory tract plays a vital role in the respiratory system, comprising several structures that facilitate air intake and prepare air for…
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