Nasopharynx ::
It is the junction between the oral and the nasal cavity or the oesophagus and the larynx it is guarded by epiglottis which closes the passage of air while swallowing food
Larynx ::
It is the voice box which is interposed to prevent the entry of food material in the trachea it has a prominent thyroid cartilage above and cricoid cartilage below with cricothyroid membrane in between them The thyroid gland is situated over these cartilages other cartilages are epiglottis arytenoid conniculate and cuneiform
The epiglottis is large leaf shaped piece of elastic cartilage the stem of epiglottis is attached to thyroid cartilage but leaf portion is unattached and free to move During swallowing the larynx rises which causes free edge of epiglottis to move down and form a lid over glottis the glottis contains pair of folds of mucus membrane the larynx is closed off and liquids and food enter into esophagus the lining of larynx inferior to vocal folds is pseudostratified ciliated columnar epithelium the cilia helps trap dust which is not removed in upper passages
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