Movements of GIT MCQs With Answer

Understanding the movements of GIT is essential for B.Pharm students preparing for pharmacology and physiology exams. This concise guide focuses on gastrointestinal motility mechanisms—peristalsis, segmentation, tonic contractions, migrating motor complex (MMC), receptive relaxation—and their control by the enteric nervous system, interstitial cells of Cajal, autonomic inputs, neurotransmitters and gut hormones. It also links clinical pharmacology: prokinetics, anticholinergics, opioids and motility disorders. Emphasis is on how drugs alter slow waves, spike potentials and transit times, and on pathophysiology of ileus, constipation and diarrhea. Clear, exam-oriented MCQs below reinforce concepts and drug correlations for effective revision. Now let’s test your knowledge with 50 MCQs on this topic.

Q1. Which pacemaker cells generate slow waves in the gastrointestinal tract?

• Enterochromaffin cells
• Interstitial cells of Cajal
• Paneth cells
• Goblet cells

Correct Answer: Interstitial cells of Cajal

Q2. The primary function of peristalsis in the small intestine is:

• Segmentation of chyme into small particles
• Mixing chyme with digestive enzymes only
• Propulsive movement to advance luminal contents
• Absorption of water and electrolytes

Correct Answer: Propulsive movement to advance luminal contents

Q3. Which enteric plexus primarily coordinates gut motility?

• Submucosal (Meissner) plexus
• Myenteric (Auerbach) plexus
• Cardiac plexus
• Hypogastric plexus

Correct Answer: Myenteric (Auerbach) plexus

Q4. Segmentation contractions mainly serve to:

• Propel feces quickly through the colon
• Mix luminal contents and enhance absorption
• Initiate the migrating motor complex
• Cause tonic closure of sphincters

Correct Answer: Mix luminal contents and enhance absorption

Q5. The migrating motor complex (MMC) is most active during:

• Postprandial fed state
• Fasting state between meals
• During gastric emptying of solids only
• Immediately after a fatty meal

Correct Answer: Fasting state between meals

Q6. Motilin primarily stimulates which gastrointestinal activity?

• Inhibition of gastric secretion
• Initiation of MMC and gastric motility
• Increase in colonic haustration
• Promotion of bicarbonate secretion

Correct Answer: Initiation of MMC and gastric motility

Q7. Which neurotransmitter is the major excitatory mediator of smooth muscle contraction in the gut?

• Nitric oxide
• Acetylcholine
• Vasoactive intestinal peptide (VIP)
• Dopamine

Correct Answer: Acetylcholine

Q8. Nitric oxide in the GI tract primarily causes:

• Smooth muscle contraction
• Sphincter relaxation and inhibition of motility
• Enhanced peristalsis
• Increased gastric acid secretion

Correct Answer: Sphincter relaxation and inhibition of motility

Q9. Slow waves in GI smooth muscle determine:

• The strength of contraction only
• The maximal frequency of contractions
• Hormone release from enteroendocrine cells
• Rate of epithelial cell turnover

Correct Answer: The maximal frequency of contractions

Q10. Spike potentials in GI smooth muscle are caused by:

• Opening of voltage-gated calcium channels leading to contraction
• Activation of chloride channels causing hyperpolarization
• Release of acetylcholine from endocrine cells
• Passive diffusion of sodium across tight junctions

Correct Answer: Opening of voltage-gated calcium channels leading to contraction

Q11. Receptive relaxation of the stomach involves which mechanism?

• Local myogenic reflex only
• Vago-vagal reflex mediated by the dorsal vagal complex
• Direct action of gastrin on smooth muscle to contract
• Sympathetic stimulation increasing tone

Correct Answer: Vago-vagal reflex mediated by the dorsal vagal complex

Q12. Which hormone slows gastric emptying in response to fats in the duodenum?

• Gastrin
• Cholecystokinin (CCK)
• Motilin
• Secretin

Correct Answer: Cholecystokinin (CCK)

Q13. Auerbach plexus damage would most likely cause:

• Increased gastric acid secretion
• Impaired peristalsis and motility disorders
• Excessive fluid secretion into lumen
• Hyperactivity of the colon only

Correct Answer: Impaired peristalsis and motility disorders

Q14. Which drug is a D2 receptor antagonist used as a prokinetic agent?

• Metoclopramide
• Loperamide
• Atropine
• Omeprazole

Correct Answer: Metoclopramide

Q15. Erythromycin increases GI motility by acting as an agonist at:

• Serotonin 5-HT3 receptors
• Motilin receptors
• Muscarinic M3 receptors
• Beta-adrenergic receptors

Correct Answer: Motilin receptors

Q16. Opioids cause constipation primarily by:

• Stimulating enteric serotonin release
• Inhibiting enteric neuronal activity and decreasing peristalsis
• Increasing secretion of chloride into the lumen
• Blocking gastric acid secretion

Correct Answer: Inhibiting enteric neuronal activity and decreasing peristalsis

Q17. Cisapride (removed in many markets) exerted prokinetic effects by:

• Blocking D2 receptors
• Stimulating 5-HT4 receptors to enhance ACh release
• Inhibiting acetylcholinesterase in the gut
• Antagonizing muscarinic receptors

Correct Answer: Stimulating 5-HT4 receptors to enhance ACh release

Q18. Which condition is characterized by aganglionic colon leading to tonic contraction and obstruction?

• Peptic ulcer disease
• Hirschsprung disease
• Crohn’s disease
• Ulcerative colitis

Correct Answer: Hirschsprung disease

Q19. The peristaltic reflex involves sensing by:

• Submucosal chemoreceptors only
• Intrinsic primary afferent neurons in the enteric nervous system
• CNS only via vagal fibers
• Adrenal medulla catecholamines

Correct Answer: Intrinsic primary afferent neurons in the enteric nervous system

Q20. Which autonomic input generally inhibits gastrointestinal motility?

• Parasympathetic stimulation via vagus
• Sympathetic stimulation via splanchnic nerves
• Enteric nervous stimulation exclusively
• Somatic motor activation

Correct Answer: Sympathetic stimulation via splanchnic nerves

Q21. Bulk-forming laxatives relieve constipation by:

• Stimulating enteric neurons directly
• Absorbing water to increase stool bulk and stimulate peristalsis
• Inhibiting colonic smooth muscle tone
• Blocking sodium channels in the colon

Correct Answer: Absorbing water to increase stool bulk and stimulate peristalsis

Q22. Secretin primarily affects motility by:

• Speeding gastric emptying of solids
• Stimulating pancreatic bicarbonate and slowing gastric emptying
• Directly contracting ileal smooth muscle
• Enhancing colonic mass movements

Correct Answer: Stimulating pancreatic bicarbonate and slowing gastric emptying

Q23. A drug that inhibits acetylcholinesterase in the gut would be expected to:

• Decrease gut motility
• Increase acetylcholine and enhance motility
• Block muscarinic receptors
• Stimulate nitric oxide production

Correct Answer: Increase acetylcholine and enhance motility

Q24. Which of the following best describes colonic mass movements?

• Continuous segmentation contractions in the rectum
• Infrequent powerful peristaltic waves that move fecal matter long distances
• MMC-like activity in the colon during fasting
• Small intestine-specific mixing contractions

Correct Answer: Infrequent powerful peristaltic waves that move fecal matter long distances

Q25. The ileocecal valve function is promoted by:

• Distension of the ileum causing relaxation of the valve
• Cecal distension causing reflex contraction of the valve
• Low colonic pressure opening the valve
• Constipation relaxing the valve

Correct Answer: Cecal distension causing reflex contraction of the valve

Q26. Which receptor activation increases smooth muscle contraction via increased intracellular cGMP?

• Muscarinic M3 receptor
• Nitric oxide stimulating guanylate cyclase
• Beta-2 adrenergic receptor
• Dopamine D2 receptor

Correct Answer: Nitric oxide stimulating guanylate cyclase

Q27. Gastrin at physiological concentrations mainly affects motility by:

• Decreasing esophageal peristalsis
• Stimulating gastric motility and lower esophageal sphincter tone
• Inhibiting pancreatic secretion
• Causing colonic relaxation

Correct Answer: Stimulating gastric motility and lower esophageal sphincter tone

Q28. Which ion is most important for excitation-contraction coupling in GI smooth muscle spike potentials?

• Sodium
• Calcium
• Chloride
• Potassium

Correct Answer: Calcium

Q29. Which clinical condition is associated with delayed gastric emptying?

• Dumping syndrome
• Gastroparesis
• Acute cholera
• Short bowel syndrome

Correct Answer: Gastroparesis

Q30. Loperamide reduces diarrhea primarily by:

• Stimulating serotonin release
• Activating peripheral opioid receptors to decrease intestinal motility
• Blocking chloride secretion into the gut lumen
• Inhibiting intestinal bacterial growth

Correct Answer: Activating peripheral opioid receptors to decrease intestinal motility

Q31. The fed pattern of small intestinal motility differs from MMC by showing:

• Long uninterrupted periods of quiescence
• Irregular, continuous contractions for mixing and absorption
• Phase III high-amplitude activity every 90 minutes
• Complete cessation of peristalsis

Correct Answer: Irregular, continuous contractions for mixing and absorption

Q32. Which of the following decreases lower esophageal sphincter (LES) tone and can promote reflux?

• Metoclopramide
• Neostigmine
• Anticholinergics like atropine
• Proton pump inhibitors

Correct Answer: Anticholinergics like atropine

Q33. The primary effect of serotonin (5-HT) released from enterochromaffin cells is to:

• Directly digest proteins
• Activate intrinsic sensory neurons to modulate motility and secretion
• Inhibit afferent vagal signaling
• Reduce intestinal blood flow

Correct Answer: Activate intrinsic sensory neurons to modulate motility and secretion

Q34. An ileus after abdominal surgery is mainly due to:

• Excessive motilin release
• Inhibition of enteric neurons and sympathetic activation causing reduced motility
• Enhancement of parasympathetic activity
• Overproduction of gastric acid

Correct Answer: Inhibition of enteric neurons and sympathetic activation causing reduced motility

Q35. Which pharmacological class is used acutely to stimulate colonic evacuation for bowel preparation?

• Bulk-forming laxatives
• Stimulant laxatives like bisacodyl
• Antidiarrheals like loperamide
• Proton pump inhibitors

Correct Answer: Stimulant laxatives like bisacodyl

Q36. Which of the following best explains ileocecal reflex control during increased ileal motility?

• Ileocecal valve opens to allow reflux of colonic contents
• Ileocecal valve relaxes to prevent ileal emptying
• Ileocecal valve relaxes facilitating ileal emptying into cecum
• Ileocecal valve is unaffected by ileal activity

Correct Answer: Ileocecal valve relaxes facilitating ileal emptying into cecum

Q37. Which receptor when stimulated in the gut reduces motility and increases fluid secretion?

• Muscarinic M3
• Opioid mu receptor
• Beta-2 adrenergic receptor
• 5-HT4 receptor

Correct Answer: Opioid mu receptor

Q38. Which diagnostic test can assess gastric emptying and motility quantitatively?

• Esophagogastroduodenoscopy
• Gastric emptying scintigraphy
• Sigmoidoscopy
• Hydrogen breath test

Correct Answer: Gastric emptying scintigraphy

Q39. The defecation reflex is primarily initiated by:

• Sympathetic stimulation of the sigmoid colon
• Distension of the rectal wall activating stretch receptors
• Secretin release from duodenum
• Gastrin secretion after a meal

Correct Answer: Distension of the rectal wall activating stretch receptors

Q40. Secretagogues that increase intestinal secretion and motility are useful in treating:

• Diarrhea due to infection
• Chronic constipation (e.g., lubiprostone activates Cl- channels)
• Gastroesophageal reflux disease
• Peptic ulcer bleeding

Correct Answer: Chronic constipation (e.g., lubiprostone activates Cl- channels)

Q41. Which statement about haustration in the colon is correct?

• Haustrations are persistent fixed folds formed by circular muscle contraction
• Haustrations are transient sacculations produced by segmentation-like contractions
• Haustrations are exclusively found in the small intestine
• Haustrations prevent any fecal propulsion

Correct Answer: Haustrations are transient sacculations produced by segmentation-like contractions

Q42. Which ion channel activity underlies slow wave generation in ICCs?

• Voltage-gated sodium channels only
• Pacemaker currents including nonselective cation channels and Ca2+-activated channels
• Chloride channel closure exclusively
• Sodium-potassium ATPase pump alone

Correct Answer: Pacemaker currents including nonselective cation channels and Ca2+-activated channels

Q43. Which pharmacologic agent is likely to worsen constipation in a patient with chronic pain?

• Laxatives like polyethylene glycol
• Opioid analgesics like morphine
• Prokinetic agents like metoclopramide
• Motilin agonists like erythromycin

Correct Answer: Opioid analgesics like morphine

Q44. A drug that blocks 5-HT3 receptors in the gut is most likely to:

• Increase intestinal secretion and motility
• Reduce visceral pain and slow transit in some settings
• Act as a strong prokinetic in constipation
• Stimulate motilin release

Correct Answer: Reduce visceral pain and slow transit in some settings

Q45. Which of the following increases small intestinal transit time (faster transit)?

• Anticholinergic drugs
• Sympathetic stimulation
• Prokinetic agents like cisapride or metoclopramide
• Opioid therapy

Correct Answer: Prokinetic agents like cisapride or metoclopramide

Q46. The enteric nervous system can function independently of the central nervous system because it contains:

• Only motor neurons
• A complete network of sensory, interneurons and motor neurons
• No synapses and only reflex arcs to the spinal cord
• Myelinated vagal fibers within the gut wall

Correct Answer: A complete network of sensory, interneurons and motor neurons

Q47. Which substance released during inflammation can directly alter gut motility leading to diarrhea?

• Endorphins
• Prostaglandins and cytokines
• Ghrelin only
• Insulin

Correct Answer: Prostaglandins and cytokines

Q48. Which physiologic change accelerates gastric emptying of liquids?

• High fat content in the duodenum
• Low osmolarity and hypotonic fluids
• Hyperosmolar glucose solution
• Cold temperature of the meal only

Correct Answer: Low osmolarity and hypotonic fluids

Q49. Which clinical drug enhances upper GI motility and also increases LES tone, useful for GERD?

• Atropine
• Metoclopramide
• Loperamide
• Diphenoxylate

Correct Answer: Metoclopramide

Q50. In ulcerative colitis exacerbation, colonic motility is typically:

• Decreased leading to constipation
• Increased with frequent urgent bowel movements and reduced transit time
• Unchanged compared to healthy colon
• Converted into MMC-dominant pattern only

Correct Answer: Increased with frequent urgent bowel movements and reduced transit time

G S Sachin

I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.

Mail- Sachin@pharmacyfreak.com