Referred to as the voice box and situated at the bottom of the vocal tract between the vocal cords and the oral cavity, it is part of the cartilaginous air passage structure, located above the trachea and below the pharynx, that houses the vocal folds and the various muscles serving laryngeal vocal mechanisms. Pitch and volume are generated in the larynx, with articulation deriving from the use of the lips, palate, teeth and tongue. It also serves as a valve to regulate airflow from the respiratory system. During swallowing, the larynx, together with the epiglottis, closes to prevent liquids and solids from entering the lungs. At about three months-of-age in the human, the larynx descends to a position in the pharynx, resulting in the elimination of the seal between the velum and the epiglottis, thus opening the airway to the nose, allowing breathing through the mouth instead of just the nose, and improving the ability to regulate sub-glottal pressure during crying. As a consequence of the descent, the infant can no longer breathe and ingest simultaneously.
See Adolescent voice change, Anterior commissure, Articulation, Crying, Epiglottis, Fundamental frequency (F₀), Glottal, Hyoid bone, Implosives, Joint capsule, Palate, Pharynx. Pitch, Vagus (or pneumogastric) nerve, Velum, Vocal folds