Free Gastrointestinal Physiology MCQs with Answers

• A. Liver
• B. Stomach
• C. Pancreas
• D. Duodenum

Explanation: Intrinsic factor is secreted by gastric parietal cells and binds vitamin B12 before its absorption in the terminal ileum.

• A. None of the aboveConsult Online Doctors
• B. Lateral and medial to food bolus
• C. Dorsal and ventral to food bolus
• D. Above and below the food bolus

Explanation: A distended segment of gut contracts above the bolus while the segment below relaxes, propelling contents forward.

• A. Intrinsic factor
• B. Secretin
• C. Motilin
• D. GIPGet Study Guides

Explanation: Intrinsic factor is produced by gastric parietal cells, not enteroendocrine cells.

• A. Chymotrypsinogen
• B. Pepsinogen
• C. Proelastase
• D. Procolipase

Explanation: Trypsin activates several pancreatic zymogens, including chymotrypsinogen, proelastase and procolipase.

• A. Gastric juice
• B. Bile in gall bladder
• C. Pancreatic juice
• D. Saliva

Explanation: Pancreatic juice is strongly alkaline because it contains a high concentration of bicarbonate, usually giving it a pH around 8.

• A. Cephalic phase of gastric secretion
• B. Pancreatic secretion of bicarbonate
• C. Bile flow from liver
• D. Mucous secretion from the Brunner's glands

Explanation: The cephalic phase of gastric secretion is initiated by sight, smell, taste or thought of food and is mediated mainly through vagal…

• A. Pancreas
• B. Duodenum
• C. Liver
• D. Stomach

Explanation: Secretin is released by S cells in the duodenal mucosa when acidic chyme enters from the stomach.

• A. Preperistalitic intestinal secretion
• B. Simultaneous action of circular and longitudinal muscles
• C. Mecharical distension
• D. Extrinsic nervous influenceOrder DNA Kits

Explanation: Mechanical distension of the intestinal wall initiates the local peristaltic reflex through the enteric nervous system.

• A. Neuro hormones
• B. Hormones
• C. Vagus
• D. Gastric

Explanation: The cephalic phase is initiated by sight, smell, taste, or thought of food and is carried mainly through vagal stimulation of gastric…

• A. Acid chyme
• B. Dilattion of intestine
• C. Protein
• D. Fat

Explanation: Acidic chyme entering the duodenum is the strongest stimulus for secretin release from S cells.

• A. Increase concentration of bile
• B. Contraction of the gallbladder
• C. Increase secretion of bile
• D. Favours acidification of bile

Explanation: Cholagogues promote gallbladder contraction and relaxation of the sphincter of Oddi, causing bile to enter the duodenum.

• A. Vagus nerve
• B. Meissners plexus
• C. Myentric plexus
• D. Parasympathetic

Explanation: The myenteric plexus mainly coordinates gastrointestinal smooth-muscle activity, including peristalsis.

• A. Brunner's glands
• B. Pyloric glands
• C. Gastric glands
• D. Fundic glands

Explanation: Fundic, or oxyntic, glands occupy most of the body and fundus of the stomach and are therefore the most numerous gastric glands.

• A. Stomach
• B. Parotid
• C. Pancrease
• D. Gall bladder

Explanation: Vagal stimulation promotes gastric, pancreatic, and gallbladder activity, but parotid secretion is controlled mainly by the…

• A. Enterokinase
• B. Trypsin
• C. Low pH
• D. Chymotrypsin

Explanation: Pepsinogen is converted to active pepsin in the strongly acidic gastric lumen, with the low pH also allowing pepsin to activate more…

• A. Is a reflex mechanism
• B. Vocal cords are closed
• C. Is a voluntary mechanism
• D. A and B

Explanation: The pharyngeal phase is an involuntary reflex triggered when the bolus reaches the pharynx, and closure of the vocal cords protects the…

• A. Hepatocytes
• B. Kupffer cells
• C. Hepatic duct
• D. The gall bladder

Explanation: Hepatocytes synthesize bile, which then flows through the hepatic ducts to the gallbladder for storage and concentration.

• A. Destruction of bacteria
• B. Neutralization of chyme
• C. Activation of pepsinogen
• D. Stimulation of pancreatic secretion

Explanation: Hydrochloric acid converts pepsinogen into pepsin, providing the acidic pH required for protein digestion.

• A. Gastrin by stomach
• B. Pancreatic enzymes
• C. Amylase by salivary gland
• D. HCL by stomach

Explanation: Histamine acts on H2 receptors of gastric parietal cells and increases hydrochloric acid secretion through cyclic AMP.

• A. Glucuronic acid
• B. Glutamine
• C. Acetyl CoA
• D. Glycine

Explanation: In hepatocytes, bilirubin is conjugated with glucuronic acid by UDP-glucuronosyltransferase, forming water-soluble bilirubin glucuronides…