Anatomy and Physiology of the Upper Digestive Tract

Vocabulary flashcards covering the anatomy and physiology of the upper digestive tract, including swallowing, salivary glands, immune structures, gut wall layers, and the stomach.

Pharynx (Rachenbereich)

The throat region that functions as a dual-purpose passage where respiratory air and ingested food run parallel before being separated.

Soft Palate (Weicher Gaumen)

A mobile anatomical structure that swings upward during swallowing to seal off the nasal cavity and prevent food or liquids from entering the nose.

Epiglottis (Kehldeckel)

A cartilaginous flap that folds downward over the entrance of the trachea during swallowing, acting like a slide to guide food safely into the esophagus.

Swallowing Reflex (Schluckreflex)

An automatic, all-or-nothing reflex triggered as soon as food is pushed backward and touches the nerve-rich posterior wall of the pharynx.

Salivary Amylase

An enzyme produced in saliva that initiates carbohydrate breakdown in the mouth.

Daily Saliva Production

The total volume of saliva produced by the salivary glands each day, amounting to approximately $500\text{--}600\,\text{ml}$.

Excretory Duct (Ausföhrungsgang)

A channel through which secretory cells of a gland transport their manufactured secretions, such as saliva, into the target cavity.

Glandula Parotis (Parotid Gland)

The main salivary gland located near the ear between the cheek muscles, which is compressed during chewing to squeeze saliva into the oral cavity.

Five Signs of Inflammation

The five classical signs of inflammation: swelling, redness, pain, warmth, and restricted function ($5.\,\text{Säule}$).

Suffix "-itis"

A medical suffix appended to an organ name to indicate inflammation, such as in parotitis, esophagitis, bronchitis, or gastritis.

Tonsils (Tonsillen / Mandeln)

Clusters of lymphoid tissue containing leukocytes located in the pharyngeal area that act as primary immune checkpoints and antigen-presenting sites.

Waldeyer's Tonsillar Ring (Waldeyerscher Rachenring)

A protective circular ring of immune defense structures at the entrance of the pharynx, consisting of the Tonsilla pharyngea, Tonsilla tubaria, Tonsilla palatina, and Tonsilla lingualis.

Adenoids (Nasenpolypen)

Enlarged tonsillar lymphoid tissue near the posterior nasal opening in children that can obstruct airflow, leading to habitual mouth breathing and hyponasal speech.

Esophagus (Ösophagus)

A muscular tube measuring approximately $25\text{--}30\,\text{cm}$ in adults that bridges the thoracic cavity to transport food swiftly from the pharynx to the stomach.

Peristalsis (Peristaltik)

An involuntary, forward-moving muscular wave driven by coordinated contractions of circular and longitudinal muscles that transports contents through the digestive tract regardless of gravity.

Mucosa (Mukosa)

The innermost epithelial layer of the digestive tract wall that contains cells producing a lubricating mucus layer to protect the wall and facilitate passage.

Submucosa

The connective tissue layer located directly beneath the mucosa that functions as a protective buffer and structural cushion.

Muscularis

The muscular wall layer responsible for peristaltic propulsion, typically composed of circular and longitudinal muscle fibers.

Serosa

The outermost smooth connective tissue layer of the digestive tract that wraps organs smoothly, allowing neighboring intestinal loops to slide past one another without friction.

Gastric Retention Time

The duration food remains stored in the stomach for chemical and mechanical processing, ranging from $20\,\text{minutes}$ up to $6\,\text{hours}$.

Gastric Juice pH

The highly acidic pH of the stomach, typically measured at $1\text{--}2$, which serves to disinfect incoming food by destroying pathogens and breaking down cell walls.

Daily Gastric Juice Production

The total volume of acidic fluid secreted by the stomach lining every day, averaging $2\text{--}3\,\text{liters}$.

Pepsin

A gastric digestive enzyme active in acidic pH that begins the breakdown of proteins into smaller components.

Cardia (Mageneingang)

The anatomical entry zone of the stomach where the terminal esophagus connects to the gastric cavity.

Fundus (Magenfundus)

The upper dome-shaped curvature of the stomach where swallowed air collects, which expands upward against the diaphragm when the stomach is very full.

Corpus (Magencorpus)

The central main body and largest anatomical region of the stomach.

Antrum (Magenantrum)

The lower, pre-pyloric chamber of the stomach that acts as an antechamber before food chyme is emptied into the small intestine.

Pylorus (Magenpförtner)

A muscular sphincter at the gastric exit that acts as a gatekeeper, metering digested chyme in small portions into the small intestine.

Gastric Mucosal Barrier

A dense protective coating of mucus produced by surface epithelial cells that shields the stomach wall from being digested by hydrochloric acid and pepsin.

Heartburn (Sodbrennen)

A burning sensation caused by the reflux of acidic stomach contents upward into the esophagus when the upper esophageal junction fails to close properly.