Digestive System Flashcards

Vocabulary-style flashcards covering the anatomy, physiology, and clinical conditions of the digestive system based on Chapter 18.

Alimentary canal

Also known as the digestive tract or gastrointestinal (GI) tract, it extends from the mouth to the anus and is approximately $9$ meters ($29$ feet) in length.

Digestion

The process of breaking down food into smaller components that can be absorbed by the body. Digestion involves both mechanical and chemical processes.

Mucosa

The innermost layer of the digestive tract wall, also known as the mucous membrane.

Submucosa

The layer of connective tissue found between the mucosa and muscularis layers in the digestive tract, containing blood vessels, lymphatics, and nerves.

Muscularis

The layer of the digestive tract wall responsible for the contraction and movement of food through peristalsis. It consists of smooth muscle tissue.

Serosa

The outermost layer of the digestive tract wall, consisting of a thin layer of connective tissue covered by a mesothelium.

Peristalsis

The rhythmic contraction of smooth muscles in the digestive tract that moves food through the system.

Uvula

A downward projection of the soft palate that, along with the soft palate, prevents food and liquid from entering the nasal cavities and assists in speech and swallowing.

Papillae

Small, nipple-like projections on the tongue and in the lining of the mouth, involved in taste perception and texture sensation.

Incisor

A type of tooth located at the front of the mouth, used for cutting and shearing food. Incisors are typically eight in total, with four in the upper jaw and four in the lower jaw.

Canine

A type of tooth located next to the incisors, used for tearing and grasping food. There are four canines in total, two in the upper jaw and two in the lower jaw. sometimes referred to as cuspid.

Premolar

A type of tooth located between the canines and molars, used for crushing and grinding food. Premolars are typically eight in total, with two in each quadrant of the mouth. sometimes referred to as bicuspids.

Molar

A type of tooth located at the back of the mouth, used for grinding and chewing food. Molars are typically twelve in total, with three in each quadrant of the mouth. or Tricuspid

Deglutition

The medical term for the process of swallowing.

Lingual frenulum

A fold of mucous membrane that helps anchor the tongue to the floor of the mouth.

Deciduous teeth

Also known as baby teeth or primary teeth; a full set equals $20$ teeth, with the first tooth typically erupting at about $6$ months.

Permanent teeth

A full set usually equals $32$ teeth, with the first tooth erupting at about $6$ years of age and the set completing between ages $17$ and $24$ years.

Dentin

The bony material that makes up the crown of a tooth and is covered by hard enamel.

Parotid glands

The largest of the salivary glands, located in front of the ear at the angle of the jaw; they become inflamed during mumps.

Salivary amylase

An enzyme contained in saliva that begins the chemical digestion of carbohydrates.

Leukoplakia

A precancerous condition of the mouth tissue.

Gingivitis

Inflammation or infection of the gums, most commonly resulting from poor oral hygiene.

Thrush

Also known as oral candidiasis, it is a yeastlike fungal infection causing "cheesy"-looking exudate over an inflamed oral mucosa.

Periodontitis

Inflammation of the periodontal membrane; it is the leading cause of tooth loss among adults.

Esophagus

The esophagus is a muscular tube that connects the throat (pharynx) with the stomach, allowing the passage of food and liquids. Each end is guarded by a muscular sphincter, The upper sphincter prevents air from entering the esophagus while the lower sphincter prevents stomach contents from returning.

Gastroesophageal Reflux Disease (GERD)

The backflow of acidic stomach contents into the esophagus, causing symptoms of heartburn and indigestion.

Barrett esophagus

A precancerous condition that may result from untreated, chronic irritation of the esophagus due to GERD.

Stomach

The stomach is a muscular sac that digests food by mixing it with gastric juices, breaking down proteins, and storing food before it moves into the small intestine. four divisions include the fundus, body, antrum, and pylorus.

Chyme

The semi-liquid substance produced when the muscular walls of the stomach mix food with gastric juice.

Rugae

Folds in the mucous membrane lining of the stomach that are visible when the stomach is empty.

Pyloric sphincter

A muscle that closes the opening of the lower part of the stomach to retain food for partial digestion. conditions for infants may include reflux, pylorospasm and pyloric stenosis.

Ulcer

An open wound caused by acid in gastric juice, often associated with infection by the bacterium Helicobacter pylori.

Small Intesines

The portion of the digestive tract between the stomach and large intestine, where most digestion and nutrient absorption occur. three different sections are the duodenum, jejunum, and ileum.

Villi

Microscopic finger-shaped projections from the surface of the mucosa into the intestinal cavity that contain blood and lymph capillaries.

Lacteal

A lymph capillary found within a single villus of the small intestine.

Enteritis

Inflammation of the small intestine.

Cholelithiasis

The condition of having gallstones, which are calculi made of crystallized bile pigments and calcium salts.

Hepatitis

Inflammation of the liver, often caused by viral infections, alcohol consumption, or toxins.

Cirrhosis

Degeneration of liver tissue involving the replacement of normal tissue with fibrous and fatty tissue.

Pancreatic islets

Also known as islets of Langerhans, these cells are not connected to pancreatic ducts and secrete the hormones glucagon and insulin into the blood.

Large Intestines

The final part of the digestive system where water is absorbed and feces are formed before elimination. Subdivisions include the cecum, accndong colon, rectum, and anal canal.

Diverticulitis

Inflammation of atypical outpouchings (diverticula) in the large intestine.

Mesentery

An extension of the parietal peritoneum that attaches most of the small intestine to the posterior abdominal wall.

Ascites

Abnormal accumulation of fluid in the peritoneal space, often causing bloating of the abdomen.

Hydrolysis

A process in chemical digestion where enzymes speed up reactions that add water to break large molecules into smaller molecules.

Pepsin

A gastric juice enzyme that begins the partial digestion of proteins in the stomach.

Fractal geometry

A concept used by scientists to describe surfaces with a seemingly infinite area, such as the lining of the small intestine.