Questions with Correct Verified Answers – Latest
Update 2026/ Rated A+
1. Which cells are the origin of electrical slow wave activity in
gastrointestinal smooth muscle?
• A. The smooth muscle of the circular muscle layer
• B. The smooth muscle of the longitudinal muscle layer
• C. The interstitial cells of Cajal
• D. The myenteric plexus
Correct Answer: C
Rationale: The interstitial cells of Cajal are the pacemaker cells of
the GI tract that generate the electrical slow wave (basal electrical
rhythm). These cells are located between the longitudinal and
circular muscle layers and coordinate smooth muscle contraction .
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,2. Which of the following factors will DECREASE gastric
emptying?
• A. Distension of the pyloric antrum
• B. Parasympathetic stimulation
• C. The presence of fats in the duodenum
• D. A fall in the pH of chyme in the stomach
Correct Answer: C
Rationale: The presence of fats in the duodenum stimulates the
release of cholecystokinin (CCK), which inhibits gastric emptying
via the enterogastric reflex. Distension of the pyloric antrum and
parasympathetic stimulation INCREASE gastric emptying .
3. Which hormone slows gastric emptying?
• A. Gastrin
• B. Motilin
• C. Cholecystokinin
• D. Ghrelin
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,Correct Answer: C
Rationale: CCK is released by I-cells in the duodenum in response to
fats and slows gastric emptying to allow adequate time for fat
digestion and absorption in the small intestine .
4. The migrating motor complex (MMC) in humans:
• A. Occurs only in the small intestine
• B. Requires an intact intrinsic nervous system for coordinated
propagation
• C. Is the result of food-mediated distension of the small
intestine
• D. Mixes intestinal contents with bile and digestive enzymes
Correct Answer: B
Rationale: The MMC requires an intact intrinsic nervous system for
coordinated propagation. It occurs in the stomach and small
intestine during fasting and is responsible for clearing undigested
material .
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, 5. Which of the following processes occurs throughout most of the
alimentary canal?
• A. Ingestion
• B. Propulsion
• C. Segmentation
• D. Absorption
Correct Answer: B
Rationale: Propulsion (peristalsis) occurs throughout most of the
alimentary canal from the esophagus to the rectum. Ingestion only
occurs in the mouth, segmentation is most prominent in the small
intestine, and absorption is concentrated in the small intestine .
6. Which of the following statements about reflexes in the GI
tract is FALSE?
• A. Short reflexes are provoked by nerves near the GI tract
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