Larynx Anatomy Quiz

Study Notes

The larynx, also known as the voice box, is an organ in the neck involved in breathing, producing sound, and protecting the trachea against food aspiration.
The larynx houses the vocal cords, which manipulate pitch and volume, essential for phonation.
The larynx is situated just below where the tract of the pharynx splits into the trachea and esophagus.
The word 'larynx' comes from the Ancient Greek word 'lárunx', meaning 'throat' or 'gullet'.

The larynx consists of cartilages attached to each other and surrounding structures by muscles or fibrous and elastic tissue components.
The larynx is lined by a ciliated columnar epithelium, except for the vocal folds.
The cavity of the larynx extends from its triangle-shaped inlet to the epiglottis and to the circular outlet at the lower border of the cricoid cartilage.

The mucous membrane lining the larynx forms two pairs of lateral folds that project inward into its cavity.
The upper folds are called the vestibular folds or false vocal cords, which play no part in vocalization.
The lower pair of folds are known as the vocal cords, which produce sounds needed for speech and other vocalizations.
The slit-like space between the left and right vocal cords is called the rima glottidis, the narrowest part of the larynx.

In adult humans, the larynx is found in the anterior neck at the level of the cervical vertebrae C3–C6.
The larynx connects the inferior part of the pharynx (hypopharynx) with the trachea.
The laryngeal skeleton consists of nine cartilages: three single (epiglottic, thyroid, and cricoid) and three paired (arytenoid, corniculate, and cuneiform).
The hyoid bone is not part of the larynx, though the larynx is suspended from the hyoid.

The muscles of the larynx are divided into intrinsic and extrinsic muscles.
Intrinsic muscles are responsible for controlling sound production, including respiratory and phonatory muscles.
Extrinsic muscles support and position the larynx within the mid-cervical region.

The larynx is innervated by branches of the vagus nerve on each side.
Sensory innervation to the glottis and laryngeal vestibule is by the internal branch of the superior laryngeal nerve.
Motor innervation to all other muscles of the larynx and sensory innervation to the subglottis is by the recurrent laryngeal nerve.

In newborn infants, the larynx is initially at the level of the C2–C3 vertebrae, and is further forward and higher relative to its position in the adult body.
The larynx descends as the child grows.