Digestive System Anatomy and Physiology

Vocabulary flashcards covering the organs, histology, functions, and digestive processes of the human gastrointestinal system based on the lecture materials.

Mesenteries

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

Greater omentum

A structure lying anterior to abdominal viscera that provides padding, protection, insulation, and energy reserves.

Mucosa

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

Enteroendocrine cells (G cells)

Cells in the pyloric glands that secrete gastrin.

Fundus

The region of the stomach that accommodates the meal and can expand to $4\times$ its original volume.

Antrum

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

Pylorus

The region containing the pyloric sphincter which separates the stomach from the small intestine.

Peristalsis

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

Segmentation

Rhythmic cycles of activity that churn and fragment a bolus.

Parietal cells

Cells in the gastric glands that secrete intrinsic factor and $HCl$.

Chief cells

Cells in the gastric glands that secrete pepsinogen.

Cephalic phase

The phase of gastric secretion where the CNS prepares the stomach to receive ingested material.

Gastric phase

The phase of gastric secretion that begins with the arrival of food in the stomach, lasting $3-4$ hours.

Duodenum

The first subdivision of the small intestine, measuring approximately $25\,cm$ in length.

Plicae

Transverse folds of the intestinal lining.

Lacteals

Terminal lymphatics located in the intestinal villi.

Gastroileal reflex

A reflex that triggers the relaxation of the ileocecal valve.

Liver lobule

The basic functional unit of the liver.

Gallbladder

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

Micelles

Lipid-bile salt complexes formed during chemical digestion that diffuse into intestinal epithelia.

Chylomicrons

Complexes released by intestinal epithelia into the blood during lipid absorption.

Adventitia

A layer of dense irregular connective tissue that anchors the esophagus, as it lacks a serosa.

Diverticulosis

A condition characterized by hollow pockets protruding from the outer surface of the colon.