Gastrointestinal Tract Flashcards

Questions and Answers

What are the characteristics of the Large Intestine or Colon?

Is a blind extension of the colon

Contains crypts (correct)

Has villi and plicae

Has Teniae coli (correct)

What is the function of Teniae coli?

Allows segments of colon to contract independently.

What are Haustra coli?

Sacculations between Teniae coli.

What are the functions of the colon?

Recovery of water and salt, fat-soluble vitamin absorption, and immune function. Signup and view all the answers

What is Hirschsprung's disease?

A congenital disorder of the colon causing chronic constipation. Signup and view all the answers

Describe the appendix.

Thin finger-like process, a blind extension of the colon with crypts of Lieberkuhn and extensive lymphoid tissue. Signup and view all the answers

What causes appendicitis?

Obstruction of the opening between the cecum and appendix. Signup and view all the answers

What is the origin of carcinoid tumors?

Enteroendocrine cell origin. Signup and view all the answers

Peyer's patches in the ileum are all anti ______.

mesenteric Signup and view all the answers

Describe the differences between Peyer's patches and large lymphatic nodules.

Peyer's patches are anti-mesenteric in the ileum, while large lymphatic nodules in the appendix are located all around. Signup and view all the answers

What is the structure of the rectum's mucosa?

Thick, with simple columnar epithelium and prominent veins. Signup and view all the answers

What is the epithelial structure of the anus?

Stratified squamous epithelium. Signup and view all the answers

Study Notes

Large Intestine (Colon)

Lacks villi and plicae, featuring only crypts.
Structured with the same layers: epithelium, lamina propria, and muscularis.
Teniae coli consist of evenly spaced bands of the outer longitudinal layer of muscularis externa.

Teniae coli Functions

Facilitates contraction of the large intestine.
Enables segments of the colon to contract independently.
Contributes to fecal compaction and general peristalsis.

Haustra coli

Sacculations occurring between teniae coli, allowing parts of the colon to function independently.

Function of the Colon

Principal role includes the recovery of water and salts.
Employs Na+/K+ activated ATPase-driven transport system for fat-soluble substances.
Bacterial activity generates vitamins and results in large amounts of white blood cells.
Displays a thin muscularis mucosae and thick muscularis externa.

Hirschsprung's Disease (Mega-colon)

Congenital disorder characterized by the absence of ganglion cells, leading to chronic constipation due to non-migrated neural crest ganglia.

Appendix

A thin, finger-like blind extension of the colon stemming from the embryonic cecum.
Lacks villi; contains crypts of Lieberkuhn with columnar and goblet cells.
Rich in extensive lymphoid tissue and large lymphatic aggregates.
Features a thick submucosa.

Appendicitis

Occurs due to obstruction of the opening between the cecum and the appendix.

Carcinoid Tumors

Arise from enteroendocrine cells; typically found in the gastrointestinal tract.

Peyer's Patches vs. Lymphatic Nodules

Peyer's patches in the ileum are located anti-mesenteric (on one side), while large lymphatic nodules in the appendix surround the entire structure.

Rectum

Features thick mucosa and simple columnar epithelium.
Contains prominent veins and long crypts primarily composed of goblet cells.

Anus

Composed of stratified squamous epithelium and contains prominent veins.
Similar to the rectum, it has long crypts with a predominance of goblet cells.

Summary of Digestive Functions

Digestive processes include absorption, digestion, and waste elimination, with notable roles played by each component of the gastrointestinal tract.

Description

Explore the essential components of the gastrointestinal tract focusing on the colon, appendix, rectum, and anal canal. These flashcards provide concise definitions and key functions, helping reinforce your understanding of anatomy and physiology in this region.