 They are so-named because the glottis, the openable space between the vocal folds internal to the larynx, separates the two cavities.The supraglottal cavity or the orinasal cavity is divided into an oral subcavity (the cavity from the glottis to the lips excluding the nasal cavity) and a nasal subcavity (the cavity from the velopharyngeal port, which can be closed by raising the velum).The subglottal cavity consists of the trachea and the lungs.