Digestive System Anatomy and Histology

Comprehensive vocabulary flashcards covering the anatomy and histology of the digestive system, including the GI tract layers, accessory organs, and abdominal membranes.

Alimentary canal (gastrointestinal or GI tract)

The continuous muscular tube that digests and absorbs food, consisting of the mouth, pharynx, esophagus, stomach, small intestine, and large intestine.

Accessory digestive organs

Organs including teeth, tongue, gallbladder, salivary glands, liver, and pancreas that assist in the digestive process.

Visceral peritoneum

The serous membrane found on the external surface of most digestive organs.

Parietal peritoneum

The serous membrane that lines the abdominal body wall.

Peritoneal cavity

The fluid-filled space between the visceral and parietal peritoneum that lubricates mobile organs.

Mesentery

A double layer of peritoneum that provides routes for vessels and nerves, holds organs in place, and stores fat.

Retroperitoneal organs

Organs that lie posterior to the peritoneum.

Intraperitoneal (peritoneal) organs

Organs that are completely surrounded by the peritoneum.

Mucosa

The innermost layer of the alimentary canal consisting of three sublayers: epithelium, lamina propria, and muscularis mucosae.

Muscularis mucosae

A sublayer of the mucosa consisting of smooth muscle that produces local movements.

Submucosa

A layer of dense connective tissue containing blood and lymphatic vessels, lymphoid follicles, and the submucosal nerve plexus.

Muscularis externa

The tunic responsible for segmentation and peristalsis, consisting of inner circular and outer longitudinal layers and the myenteric nerve plexus.

Serosa

The visceral peritoneum layer; in the esophagus, it is replaced by fibrous adventitia.

Oral (buccal) cavity

The space bounded by the lips, cheeks, palate, and tongue.

Hard palate

The anterior portion of the palate formed by the palatine bones and the palatine processes of the maxillae.

Uvula

The projection that hangs downward from the free edge of the soft palate.

Filiform papillae

Whitish structures that give the tongue roughness and provide friction.

Fungiform papillae

Reddish structures scattered over the surface of the tongue.

Circumvallate (vallate) papillae

A V-shaped row of papillae located at the back of the tongue.

Extrinsic salivary glands

The parotid, submandibular, and sublingual glands.

Deciduous teeth

The 20 primary teeth that erupt between 6 and 24 months of age and fall out between 6 and 12 years of age.

Permanent teeth

The 32 teeth that replace deciduous teeth; all except the third molars typically erupt by the end of adolescence.

Esophageal hiatus

The point where the esophagus pierces the diaphragm.

Cardia

The cardiac region of the stomach that surrounds the cardiac orifice.

Fundus

The dome-shaped region of the stomach located beneath the diaphragm.

Pylorus

The region of the stomach continuous with the duodenum through the pyloric valve (sphincter).

Lesser omentum

A peritoneal fold extending from the liver to the lesser curvature of the stomach.

Greater omentum

A peritoneal fold draping from the greater curvature anterior to the small intestine.

Inner oblique layer

The third layer of smooth muscle in the stomach's muscularis externa that allows it to churn and physically break down food.

Duodenum

The retroperitoneal section of the small intestine where the bile duct and main pancreatic duct enter.

Falciform ligament

A structure that separates the right and left lobes and suspends the liver from the diaphragm and abdominal wall.

Round ligament (ligamentum teres)

The remnant of the fetal umbilical vein found along the free edge of the falciform ligament.

Porta hepatis

The site where the hepatic artery and vein enter or leave the liver.

Bile duct

The duct formed by the union of the common hepatic duct and the cystic duct.

Gallbladder

A thin-walled muscular sac that stores and concentrates bile by absorbing water and ions.

Pancreatic islets

The endocrine portion of the pancreas that secretes insulin and glucagon.

Acini

Clusters of secretory cells in the pancreas that produce pancreatic juice.

Teniae coli

Three bands of longitudinal smooth muscle found in the muscularis of the large intestine.

Haustra

Pocketlike sacs in the large intestine caused by the tone of the teniae coli.

Epiploic appendages

Fat-filled pouches of visceral peritoneum located on the large intestine.