Pharynx & Esophagus Lecture

Vocabulary flashcards covering key terms and structures related to the pharynx, esophagus, and swallowing process.

Pharynx

Muscular throat region that conducts both air and swallowed material; lined with moist stratified squamous epithelium.

Nasopharynx

Superior portion of the pharynx that opens to the nasal cavity; houses the pharyngeal tonsils and the auditory (Eustachian) tube openings.

Oropharynx

Middle portion of the pharynx located posterior to the oral cavity; contains palatine and lingual tonsils.

Laryngopharynx

Inferior pharyngeal segment opening to both the larynx (airway) and esophagus (digestive tract).

Esophagus

Muscular tube posterior to the trachea that transports the swallowed bolus from pharynx to stomach via peristalsis.

Upper Esophageal Sphincter (UES)

Circular muscle at the pharynx-esophagus junction that remains contracted except during swallowing to prevent air entry and reflux.

Lower Esophageal Sphincter (LES)

Circular muscle at the esophagus-stomach junction that prevents acidic gastric contents from refluxing into the esophagus.

Heartburn (Esophageal Reflux)

Burning sensation caused by LES failure, allowing acidic stomach contents to enter and irritate the esophagus.

Stratified Squamous Epithelium (Moist)

Protective, multilayered lining of mouth, pharynx, and esophagus with minimal keratinization; resists abrasion.

Mucosa

Innermost digestive-tract layer composed of epithelium, lamina propria, and muscularis mucosae.

Submucosa

Loose connective tissue layer beneath the mucosa containing blood vessels, nerves, and glands.

Muscularis Externa

Two smooth-muscle layers (inner circular, outer longitudinal) responsible for peristaltic movement.

Adventitia

Outer connective-tissue covering of the esophagus anchoring it to surrounding structures.

Deglutition

The act of swallowing, moving a bolus from the oral cavity to the stomach.

Bolus

Soft mass of chewed food or liquid prepared for swallowing.

Peristalsis

Wavelike contraction of circular and longitudinal muscle layers propelling contents through the digestive tract.

Epiglottis

Cartilaginous flap that folds over the glottis during swallowing to direct food away from the airway.

Glottis

Opening into the larynx; closed by the epiglottis during swallowing.

Pharyngeal Tonsils (Adenoids)

Lymphoid tissue in the nasopharynx involved in immune defense.

Palatine Tonsils

Paired lymphoid tissues on either side of the oropharynx that help protect against ingested pathogens.

Lingual Tonsils

Lymphoid nodules at the base of the tongue contributing to immune surveillance.

Auditory (Eustachian) Tube

Air-filled passage from nasopharynx to middle ear that equalizes pressure across the tympanic membrane.

Esophageal Hiatus

Opening in the diaphragm through which the esophagus passes to reach the stomach.

Esophageal Constrictor Muscles

Pharyngeal muscles that contract sequentially to push the bolus into the esophagus.