Gastrointestinal Tract Flashcards

Study the gastrointestinal tract from esophagus to anal canal, including wall layers, blood supply, innervation, and digestion.

Card 1 of 30Question

What is the gastrointestinal tract?

A continuous muscular tube extending from the mouth to the anus that transports, digests, and absorbs ingested material.

In This Section

1. What is the gastrointestinal tract?

A continuous muscular tube extending from the mouth to the anus that transports, digests, and absorbs ingested material.

2. What are the major anatomical divisions of the gastrointestinal tract?

The oral cavity, pharynx, esophagus, stomach, small intestine, large intestine, rectum, and anal canal.

3. What are the four principal layers of the gastrointestinal wall?

Mucosa, submucosa, muscularis externa, and serosa or adventitia.

4. What are the three components of the gastrointestinal mucosa?

Epithelium, lamina propria, and muscularis mucosae.

5. Which gastrointestinal wall layer contains larger blood vessels, lymphatics, and the submucosal nerve plexus?

The submucosa.

6. What is the usual arrangement of smooth muscle layers in the gastrointestinal muscularis externa?

An inner circular layer and an outer longitudinal layer.

7. Which additional smooth muscle layer is present in the stomach?

An inner oblique layer.

8. What is the difference between serosa and adventitia in the gastrointestinal wall?

Serosa is a visceral peritoneal covering, whereas adventitia is connective tissue anchoring an organ to surrounding structures.

9. Which gastrointestinal organ connects the pharynx to the stomach?

The esophagus.

10. At approximately which vertebral level does the esophagus pass through the diaphragm?

T10, through the esophageal hiatus.

11. What are the four major anatomical regions of the stomach?

Cardia, fundus, body, and pyloric part.

12. Which structure regulates the passage of gastric contents into the duodenum?

The pyloric sphincter.

13. What are the three anatomical divisions of the small intestine?

Duodenum, jejunum, and ileum.

14. Which part of the small intestine receives bile and pancreatic secretions?

The descending second part of the duodenum.

15. Which anatomical landmark marks the transition from the duodenum to the jejunum?

The duodenojejunal flexure, supported by the suspensory muscle of the duodenum.

16. Which structural features increase the absorptive surface area of the small intestine?

Circular folds, intestinal villi, and epithelial microvilli.

17. Which lymphoid structures are particularly abundant in the ileum?

Aggregated lymphoid nodules called Peyer's patches.

18. What are the principal divisions of the large intestine?

Cecum, appendix, colon, rectum, and anal canal.

19. What are the three characteristic external anatomical features of the colon?

Taeniae coli, haustra, and epiploic appendages.

20. Where is the vermiform appendix attached?

To the posteromedial wall of the cecum, inferior to the ileocecal junction.

21. Which portion of the gastrointestinal tract temporarily stores feces before defecation?

The rectum, particularly its dilated ampulla.

22. What are the two major sphincters of the anal canal?

The internal anal sphincter of smooth muscle and the external anal sphincter of skeletal muscle.

23. What distinguishes intraperitoneal from retroperitoneal gastrointestinal organs?

Intraperitoneal organs are covered by visceral peritoneum and generally suspended by mesentery; retroperitoneal organs lie posterior to the parietal peritoneum.

24. Which three unpaired branches of the abdominal aorta supply the embryological gut divisions?

The celiac trunk, superior mesenteric artery, and inferior mesenteric artery.

25. Which gastrointestinal structures are primarily supplied by the celiac trunk?

Foregut structures, including the abdominal esophagus, stomach, and proximal duodenum.

26. What is the gastrointestinal territory of the superior mesenteric artery?

The midgut, from the distal duodenum through the proximal two-thirds of the transverse colon.

27. Which gastrointestinal regions are primarily supplied by the inferior mesenteric artery?

The distal transverse colon, descending colon, sigmoid colon, and upper rectum.

28. Through which venous system does most nutrient-rich blood from the gastrointestinal tract reach the liver?

The hepatic portal venous system.

29. Which nerves provide the principal parasympathetic innervation to the gastrointestinal tract?

The vagus nerve supplies the foregut and midgut; pelvic splanchnic nerves from S2 to S4 supply the hindgut.

30. Which two intrinsic nerve plexuses regulate gastrointestinal motility and secretion?

The myenteric (Auerbach) plexus and submucosal (Meissner) plexus.