SGNA GI Anatomy and Physiology 1 — Questions and Answers
Question 1: Which sphincter separates the esophagus from the stomach and prevents gastroesophageal reflux?
- Lower esophageal sphincter (Correct answer)
- Upper esophageal sphincter
- Pyloric sphincter
- Ileocecal valve
Correct answer: Lower esophageal sphincter
The lower esophageal sphincter (LES) is a muscular ring at the gastroesophageal junction that prevents reflux of gastric contents into the esophagus.
Question 2: What is the primary function of the small intestine's villi and microvilli?
- Increase surface area for nutrient absorption (Correct answer)
- Produce digestive enzymes exclusively
- Propel food via peristalsis
- Secrete bicarbonate to neutralize acid
Correct answer: Increase surface area for nutrient absorption
Villi and microvilli (brush border) dramatically increase the absorptive surface area of the small intestine, maximizing nutrient uptake.
Question 3: The haustra are characteristic structural features of which GI organ?
- Large intestine (Correct answer)
- Small intestine
- Stomach
- Gallbladder
Correct answer: Large intestine
Haustra are the sac-like pouches that give the large intestine its characteristic segmented appearance, visible on colonoscopy.
Question 4: Which cells in the gastric mucosa secrete hydrochloric acid?
- Parietal cells (Correct answer)
- Chief cells
- G cells
- Goblet cells
Correct answer: Parietal cells
Parietal cells (oxyntic cells) in the gastric fundus and body secrete hydrochloric acid and intrinsic factor.
Question 5: What is the approximate length of the adult colon?
- 1.5 meters (Correct answer)
- 6 meters
- 0.5 meters
- 3 meters
Correct answer: 1.5 meters
The adult colon (large intestine) is approximately 1.5 meters (about 5 feet) long, extending from the ileocecal valve to the rectum.
Question 6: The ampulla of Vater is the junction where bile and pancreatic ducts empty into which structure?
- Second part of the duodenum (Correct answer)
- Jejunum
- Stomach antrum
- Common hepatic duct
Correct answer: Second part of the duodenum
The ampulla of Vater (hepatopancreatic ampulla) is located in the second portion of the duodenum and is a key landmark during ERCP.
SGNA GI Anatomy and Physiology 1
Which sphincter separates the esophagus from the stomach and prevents gastroesophageal reflux?