GPT GI Notes

Question 1

What are the 5 main functions of the digestive system?

Answer 1

Ingestion, Propulsion, Digestion, Absorption, Excretion

Question 2

What type of epithelium lines the oral cavity?

Answer 2

Stratified squamous epithelium

Question 3

What enzymes are secreted in the mouth?

Answer 3

Salivary amylase (carbohydrates) and lingual lipase (fats)

Question 4

What type of muscle is found in the esophagus?

Answer 4

Upper 1/3 skeletal muscle, middle 1/3 mixed skeletal and smooth muscle, lower 1/3 smooth muscle

Question 5

What prevents acid reflux into the esophagus?

Answer 5

Lower esophageal sphincter (LES)

Question 6

What are the major cell types in the stomach and their functions?

Answer 6

Parietal cells: secrete HCl and intrinsic factor; Chief cells: secrete pepsinogen (activated to pepsin by HCl); G cells: secrete gastrin (stimulates acid secretion)

Question 7

What epithelium lines the stomach?

Answer 7

Simple columnar epithelium (mucus-secreting)

Question 8

What is the main function of the stomach?

Answer 8

Protein digestion and chyme formation

Question 9

What are the three segments of the small intestine?

Answer 9

Duodenum, Jejunum, Ileum

Question 10

What is the main function of the small intestine?

Answer 10

Digestion and absorption of nutrients

Question 11

What cells are found in the intestinal crypts?

Answer 11

Enterocytes (absorptive cells), goblet cells (mucus), Paneth cells (antimicrobial), and stem cells

Question 12

Where are Peyer’s patches located?

Answer 12

Ileum

Question 13

What epithelium lines the small intestine?

Answer 13

Simple columnar with brush border (microvilli)

Question 14

What is the main function of the large intestine?

Answer 14

Absorption of water and electrolytes, formation of feces

Question 15

What histological feature is absent in the large intestine?

Answer 15

Villi (only crypts are present)

Question 16

What epithelium lines the large intestine?

Answer 16

Simple columnar epithelium with many goblet cells

Question 17

What are the digestive functions of the liver?

Answer 17

Bile production (emulsifies fats), detoxification, metabolism (carbs, proteins, lipids), and plasma protein synthesis

Question 18

What does the gallbladder do?

Answer 18

Stores and concentrates bile, contracts in response to CCK to release bile into the duodenum

Question 19

What are the exocrine functions of the pancreas?

Answer 19

Secretes digestive enzymes (amylase, lipase, proteases) and bicarbonate to neutralize stomach acid

Question 20

What artery supplies the foregut?

Answer 20

Celiac trunk

Question 21

What artery supplies the midgut?

Answer 21

Superior mesenteric artery (SMA)

Question 22

What artery supplies the hindgut?

Answer 22

Inferior mesenteric artery (IMA)

Question 23

What vein drains blood from the gastrointestinal tract?

Answer 23

Hepatic portal vein

Question 24

What nerve provides parasympathetic supply to the foregut and midgut?

Answer 24

Vagus nerve (cranial nerve X)

Question 25

What provides parasympathetic innervation to the hindgut?

Answer 25

Pelvic splanchnic nerves (S2-S4)

Question 26

What plexuses control gastrointestinal motility and secretion?

Answer 26

Myenteric (Auerbach's) plexus – motility; Submucosal (Meissner's) plexus – secretion and blood flow

Question 27

Where is iron absorbed?

Answer 27

Duodenum

Question 28

Where is vitamin B12 absorbed?

Answer 28

Ileum, requires intrinsic factor from parietal cells

Question 29

Where are bile salts reabsorbed?

Answer 29

Ileum

Question 30

What is the function of gastrin?

Answer 30

Stimulates HCl secretion and gastric motility

Question 31

What is the function of secretin?

Answer 31

Stimulates bicarbonate secretion from pancreas to neutralize acid

Question 32

What is the function of cholecystokinin (CCK)?

Answer 32

Stimulates gallbladder contraction and pancreatic enzyme secretion

Question 33

What is the function of motilin?

Answer 33

Initiates migrating motor complexes (MMC) during fasting to clear the gut

Question 34

What causes gastroesophageal reflux disease (GERD)?

Answer 34

Weak or incompetent lower esophageal sphincter

Question 35

What characterizes celiac disease histologically?

Answer 35

Villous atrophy, crypt hyperplasia, and increased intraepithelial lymphocytes

Question 36

What are key features of Crohn’s disease?

Answer 36

Transmural inflammation, skip lesions, granulomas, can affect any GI tract segment (often terminal ileum)

Question 37

What are key features of ulcerative colitis?

Answer 37

Continuous mucosal inflammation, begins at rectum, limited to colon