Free Gastrointestinal Physiology MCQs with Answers

• A. Creatinine
• B. Bilirubin
• C. Globulin
• D. 5 mercaptan purine

Explanation: Bile appears yellow to green mainly because of bilirubin and its oxidation product biliverdin.

• A. 4 times a day
• B. 2 times in between meals
• C. 10 times a day in fasting
• D. 8 times a day

Explanation: Bile salts undergo enterohepatic circulation repeatedly, commonly described in standard physiology texts as about eight cycles per day.

• A. Receptive relaxation
• B. Deceptive relaxation
• C. Reactive relaxation
• D. None of the above

Explanation: The proximal stomach undergoes receptive relaxation when food enters, allowing it to accommodate a meal without a major rise in…

• A. Food in the mouth
• B. Food in the stomach
• C. Sight of food
• D. Thought of food

Explanation: The cephalic phase is triggered before food reaches the stomach by sight, smell, taste, thought, or chewing of food.

• A. Isthmus
• B. Fundus
• C. Neck
• D. Gastric pit

Explanation: Chief cells are concentrated in the deeper part or base of fundic glands, where they secrete pepsinogen and gastric lipase.

• A. Pepsin
• B. Ptyalin
• C. Trypsin
• D. Cholecystokinin

Explanation: Cholecystokinin is a gastrointestinal hormone released mainly by I cells of the duodenum and jejunum in response to fats and amino acids.

• A. Pavlov's pouch
• B. Condition reflex
• C. Heidenhan's pouch
• D. None of the above

Explanation: Pavlov's pouch, a denervated or surgically isolated gastric pouch, helped demonstrate neural phases of gastric secretion, including the…

• A. Free fatty acid
• B. Higher fattery acids, diglycerides and monoglycereides
• C. Glycerol
• D. All of the above

Explanation: Bile salts form micelles that aid absorption of long-chain fatty acids and monoacylglycerols, with some diacylglycerols also included in…

• A. Hemolytic jaundice
• B. Viral hepatitis
• C. Obstructive jaundice
• D. All of the above

Explanation: Obstruction prevents bile pigments from reaching the intestine, so intestinal bacteria cannot form urobilinogen and urinary urobilinogen…

• A. Ileum
• B. Duodenum
• C. Jejunum
• D. Colon

Explanation: Most bile salts are reabsorbed by active transport in the terminal ileum and returned to the liver through the enterohepatic circulation.

• A. Gastric distension
• B. Secretin
• C. Gastrin
• D. Vagal stimulus

Explanation: Gastric distension, gastrin, and vagal stimulation promote gastric secretion through neural and hormonal pathways.

• A. Bicarbonate secretion
• B. Augments the action of CCK
• C. Gastric secretion increase
• D. Contraction of pyloric sphincter

Explanation: Secretin stimulates bicarbonate-rich pancreatic secretion and potentiates CCK, while it inhibits gastric acid secretion.

• A. All of the above
• B. Gastrin
• C. Mucin
• D. Hcl

Explanation: Parietal cells secrete hydrochloric acid and intrinsic factor. Gastrin is produced by antral G cells, while mucin is mainly secreted by…

• A. Increased gastric secretion
• B. Increased pancreatic secretion
• C. Relax lower esophageal sphincter
• D. Causes GB contraction

Explanation: CCK stimulates pancreatic enzyme secretion and gallbladder contraction, and it can relax the lower oesophageal sphincter.

• A. Large intestine
• B. Small intestine
• C. Liver
• D. Stomach

Explanation: The small intestine is the principal site for absorption because its long length, folds, villi and microvilli provide a very large…

• A. Pepsinogen
• B. Hydrochloric acid
• C. Chymotrypsinogen
• D. All of the above

Explanation: Pancreatic acinar cells release chymotrypsinogen, an inactive protease precursor that is activated in the intestine.

• A. Salivary
• B. Lacrimal
• C. Sweat
• D. Gastric

Explanation: Gastric juice secretion is approximately 1.5 to 2 litres per day, generally exceeding salivary and lacrimal secretion; sweat varies…

• A. Bile salts
• B. Cholesterol
• C. A & B
• D. Bile pigments

Explanation: Bile acids are synthesized in the liver from cholesterol and are then conjugated to form bile salts.

• A. Hepatitis
• B. Cirrhosis
• C. Increased break down of red cells
• D. Obstruction of bile canaliculi

Explanation: Increased red-cell destruction produces excess bilirubin before the liver can conjugate it, causing unconjugated hyperbilirubinemia.

• A. Secretin
• B. Lipase
• C. Maltase
• D. Antibacterial substance

Explanation: Paneth cells at the base of intestinal crypts release antimicrobial substances such as defensins and lysozyme, helping control intestinal…