Digestive System Practice Flashcards

A set of vocabulary flashcards covering the anatomy, histology, and physiological processes of the digestive system based on lecture notes.

Mesenteries

Sheets of serous membranes that support portions of the digestive tract.

Greater omentum

An abdominal structure that lies anterior to the viscera, providing padding, protection, insulation, and energy reserves.

Lesser omentum

A structure extending from the liver to the lesser curvature of the stomach.

Mucosa

The lining of the digestive tract consisting of mucous epithelium and the lamina propria.

Submucosa

A layer of dense irregular connective tissue within the digestive tract.

Muscularis externa

A middle layer of the digestive tract consisting of smooth muscle arranged in circular and longitudinal layers.

Serosa

A serous membrane covering most of the muscularis externa.

Fundus

A region of the stomach that accommodates the meal and can expand to $4 ext{X}$ its original volume.

Antrum

The stomach region that begins rhythmic contractions shortly after a meal to grind contents into small particles.

Chyme

The ground-up content of the stomach that is propelled through the pylorus into the small intestine.

Migrating motor complexes

Very strong contractions that flush contents of the stomach through the pylorus $2-3 ext{ hours}$ after a meal.

Peristalsis

Waves of muscular contraction that move a bolus along the digestive tract.

Segmentation

Muscular movements that churn and fragment a bolus.

Saliva

A watery solution containing electrolytes, buffers, glycoproteins, antibodies, and enzymes.

Pharyngeal constrictor muscles

Muscles that assist in swallowing by pushing the bolus towards the esophagus.

Adventitia

A layer of connective tissue that anchors the esophagus, which lacks a serosa.

Deglutition

The process of swallowing, which occurs in buccal, pharyngeal, and esophageal phases.

Parietal cells

Gastric gland cells responsible for secreting intrinsic factor and HCl.

Chief cells

Gastric gland cells that secrete pepsinogen.

G cells

Enteroendocrine cells in the pyloric glands that secrete gastrin.

D cells

Enteroendocrine cells in the pyloric glands that secrete somatostatin.

Secretin

A hormone that stimulates the pancreas to secrete $HCO_3^-$ and the liver to secrete bile.

Duodenum

The first subdivision of the small intestine, measuring $25 ext{ cm}$ in length.

Jejunum

The second subdivision of the small intestine, measuring $2.5 ext{ m}$ in length.

Ileum

The third subdivision of the small intestine, measuring $3.5 ext{ m}$ in length.

Plicae

Transverse folds located in the intestinal lining.

Lacteals

Terminal lymphatics found in the villi of the small intestine.

Liver lobule

The basic functional unit of the liver.

Gallbladder

A hollow, pear-shaped organ that stores, modifies, and concentrates bile.

Diverticulosis

A condition visible on the colon surface as many blue-colored hollow pockets protruding from the surface.

Micelles

Lipid-bile salt complexes formed during the digestion of lipids.

Chylomicrons

The form in which lipids are released from intestinal epithelia into the blood.

Large Intestine Vitamins

Vitamins reabsorbed in the large intestine including Vitamin K, biotin, and vitamin B5.