Thyroid, Pharynx, Esophagus, Larynx & Trachea – Key Vocabulary

A comprehensive set of vocabulary flashcards covering anatomy, blood supply, innervation, and key structures of the thyroid gland, parathyroid glands, larynx, trachea, pharynx, and cervical esophagus.

Endocrine layer (cervical viscera)

Most superficial visceral layer of the neck; contains the thyroid and parathyroid glands.

Respiratory layer (cervical viscera)

Middle visceral layer of the neck; consists of larynx and trachea.

Alimentary layer (cervical viscera)

Deep visceral layer of the neck; consists of pharynx and esophagus.

Thyroid hormone

Hormone from the thyroid gland that regulates metabolism.

Calcitonin

Thyroid hormone that lowers blood calcium levels.

Parathyroid hormone (PTH)

Hormone from parathyroid glands that raises blood calcium levels.

Thyroid gland – location

Anterior neck, deep to sternothyroid & sternohyoid, spanning C5–T1.

Thyroid lobes

Right & left anterolateral parts of the thyroid that flank larynx and trachea.

Isthmus of thyroid

Band connecting thyroid lobes anterior to 2nd–4th tracheal rings.

Pyramidal lobe

Occasionally present superior projection of thyroid toward thyroid cartilage.

Thyroid capsule

Fibrous tissue envelope surrounding the thyroid gland.

Superior thyroid artery

ECA branch supplying the upper thyroid.

Inferior thyroid artery

Branch of the thyrocervical trunk (subclavian) supplying lower thyroid.

Superior thyroid vein

Drains upper thyroid to internal jugular vein (IJV).

Middle thyroid vein

Drains middle thyroid to IJV.

Inferior thyroid veins

Drain lower thyroid to brachiocephalic veins.

Parathyroid glands – location

On posterior surface of thyroid lobes, external to thyroid capsule.

Superior parathyroid glands

Usually 1 cm above entry of inferior thyroid artery into thyroid.

Inferior parathyroid glands

Usually 1 cm below entry of inferior thyroid artery into thyroid.

Larynx – function

Voice production and airway protection during swallowing.

Larynx – location

Anterior neck opposite C3–C6; continues with trachea inferiorly.

Thyroid cartilage

Largest laryngeal cartilage; forms Adam’s apple.

Laryngeal prominence

Anterior fusion point of thyroid cartilage laminae (Adam’s apple).

Thyrohyoid membrane

Connects thyroid cartilage to hyoid bone superiorly.

Cricoid cartilage

Complete ring cartilage at C6; inferior limit of larynx.

Cricothyroid ligament

Connects thyroid & cricoid cartilages; pierced in cricothyrotomy.

Cricothyrotomy

Emergency airway through skin and cricothyroid membrane.

Epiglottic cartilage

Elastic cartilage forming the core of the epiglottis.

Epiglottis

Leaf-shaped structure that closes laryngeal inlet during swallowing.

Thyroepiglottic ligament

Anchors epiglottic cartilage to thyroid cartilage.

Arytenoid cartilages

Paired pyramidal cartilages that sit atop cricoid; move vocal folds.

Vocal process

Anterior projection of arytenoid cartilage for vocal ligament attachment.

Vocal ligaments

Elastic bands forming the core of the vocal folds.

Quadrangular membrane

Sheet between epiglottic & arytenoid cartilages; forms vestibular fold.

Vestibular ligament

Inferior free edge of quadrangular membrane; core of vestibular fold.

Ary-epiglottic ligament

Superior free edge of quadrangular membrane; core of ary-epiglottic fold.

Corniculate cartilages

Small nodules atop arytenoid apices.

Cuneiform cartilages

Small cartilages embedded in ary-epiglottic folds; not directly attached to others.

Laryngeal inlet

Opening connecting laryngopharynx to larynx.

Vestibule (larynx)

Space between laryngeal inlet and vestibular folds.

Vestibular folds

False vocal cords; inferior edge of quadrangular membrane.

Laryngeal ventricle

Lateral recess between vestibular and vocal folds.

Vocal folds

True vocal cords; sharp mucosal folds containing vocal ligaments.

Infraglottic cavity

Space between vocal folds and lower cricoid border; continuous with trachea.

Glottis

Vocal folds plus rima glottidis.

Rima glottidis

Opening between vocal folds.

Rima vestibuli

Opening between vestibular folds.

Conus elasticus

Lateral cricothyroid ligament; its free edge forms vocal ligament.

Intrinsic laryngeal muscles

Muscles that adjust vocal folds; all supplied by recurrent laryngeal nerve except cricothyroid.

Extrinsic laryngeal muscles

Supra- & infrahyoid groups that move the larynx as a whole.

Recurrent laryngeal nerve

Branch of CN X; motor to all intrinsic laryngeal muscles except cricothyroid.

External laryngeal nerve

Branch of superior laryngeal (CN X); motor to cricothyroid muscle.

Superior laryngeal artery

Branch of superior thyroid artery supplying upper larynx.

Superior laryngeal vein

Drains to superior thyroid vein from upper larynx.

Trachea

Fibrocartilaginous airway from C6 to T4; anterior to esophagus.

Pharynx

Muscular tube from cranial base to C6; splits into naso-, oro- & laryngopharynx.

Nasopharynx

Posterior to nasal cavity, above soft palate; respiratory part of pharynx.

Pharyngeal tonsils (adenoids)

Lymphoid tissue on roof/posterior wall of nasopharynx.

Opening of pharyngotympanic tube

Entrance of auditory tube on nasopharynx’s lateral wall.

Torus tubarius

Cartilage bulge surrounding auditory tube opening in nasopharynx.

Salpingopharyngeal fold

Mucosal ridge over salpingopharyngeus muscle descending from torus tubarius.

Pharyngeal recess

Lateral posterior nasopharyngeal cul-de-sac behind salpingopharyngeal fold.

Oropharynx

Part of pharynx from soft palate to superior epiglottis; digestive.

Palatine tonsils

Lymphoid masses between palatoglossal & palatopharyngeal arches.

Laryngopharynx

Posterior to larynx; from upper epiglottis to lower cricoid, joins esophagus.

Piriform fossa

Recess on each side of laryngeal inlet within laryngopharynx.

Pharyngeal constrictor muscles

Superior, middle & inferior circular muscles that propel food downward.

Pharyngeal longitudinal muscles

Palatopharyngeus, salpingopharyngeus & stylopharyngeus; elevate pharynx/larynx.

Pharyngobasilar fascia

Strong internal fascia lining constrictor muscles.

Buccopharyngeal fascia

External fascia covering pharyngeal wall.

Pharyngeal plexus

Network of CN X, CN IX & sympathetic fibers on pharyngeal wall.

Ascending pharyngeal artery

Branch of ECA supplying pharynx.

Superior esophageal sphincter

Cricopharyngeal part of inferior constrictor; guards esophageal inlet.

Cervical esophagus

Upper third (striated muscle) of esophagus in the neck.