Gastrointestinal
Question 1:
Which of the following accurately describes the function of the gut tube regions?
a) Mouth – initial digestion of lipids by salivary amylase
b) Stomach – lipid digestion by pepsin
c) Small intestine – absorption of nutrients through segmentation
d) Large intestine – initial digestion of carbohydrates and formation of faeces
e) Oesophagus – contraction of the longitudinal muscle and relaxation of the circular muscle above the bolus by peristalsis via the vagus nerve.
Question 2:
Which of the following accurately describes paracrine control in the GI tract?
a) It involves hormones released into the bloodstream such as GRP acting on ECL cells to release histamine.
b) It involves signalling molecules acting on neighbouring cells.
c) It is under voluntary control.
d) It regulates motility in the oesophagus.
e) It primarily affects the large intestine.
Question 3:
In the anatomy of the GI tract, which structures are involved in the “receptive relaxation” function of the stomach?
a) Pyloric sphincter and fundus
b) Fundus and body of the stomach
c) Body of the stomach and lower oesophageal sphincter
d) Pylorus and antrum
e) Cecum and ascending colon
Question 4:
What is the function of the retropulsion process in the stomach’s motility, and where does this process occur within the stomach?
a) It involves grinding food into smaller particles in the fundus.
b) It’s a term used for motility in the rectum during defecation.
c) It helps to propel chyme into the duodenum from the antrum.
d) It’s a function of the lower oesophageal sphincter, preventing reflux.
e) It involves squirting chyme back into the stomach from the antrum.
Question 5:
In gastric secretion, which cellular mechanism is responsible for the production of gastric acid (HCl) in the stomach, and which cell type primarily carries out this function?
a) Parietal cells located in the body produce HCl via the proton pump mechanism.
b) Chief cells located in the body and fundus produce pepsin via the production of intrinsic factor.
c) G cells are enteroendocrine cells located in the antrum that produce histamine via the release of gastrin.
d) D cells located in the fundus produce HCl via the release of somatostatin.
e) Mucous cells produce HCl via the secretion of mucus.
Question 6:
During gastric secretion, three phases are involved in response to the ingestion of a meal. Identify and explain the characteristics of the cephalic phase.
a) The cephalic phase involves the release of gastrin from G cells in the stomach.
b) It primarily occurs in the small intestine and involves nutrient absorption.
c) The cephalic phase is initiated by the sight, smell, taste, or even thought of food.
d) This phase is characterized by the release of pepsinogen from chief cells.
e) It is responsible for the production of bile in the liver.
Question 7:
Which neural mechanism controls the contraction of the external anal sphincter during voluntary defecation?
a) Sympathetic nervous system via the pudendal nerve
b) Parasympathetic nervous system via nerve roots S2-S4
c) Somatic nervous system via the pudendal nerve
d) Enteric nervous system via pelvic splanchnic nerve
e) Autonomic nervous system via ACH
Question 8:
In the small intestine, which motility pattern predominates and facilitates nutrient absorption?
a) Pendular movements
b) Haustrations
c) Mass movements
d) Peristalsis
e) Segmentation
Question 9:
In gastric secretion, what is the primary cellular mechanism responsible to produce intrinsic factor, and which cells perform this function?
a) Chief cells produce intrinsic factor via releasing pepsinogen.
b) Parietal cells produce intrinsic factor via the release of gastrin.
c) G cells produce intrinsic factor via releasing gastrin.
d) D cells produce intrinsic factor via somatostatin release.
e) Mucous cells produce intrinsic factor via mucus secretion.
Question 10:
During which phase of gastric secretion does the release of gastrin, histamine, and acetylcholine stimulate acid secretion?
a) Cephalic phase
b) Gastric phase
c) Intestinal phase
d) Fasting phase
e) Absorptive phase
Question 11:
What is the primary role of the sphincter of Oddi in the digestive process?
a) It regulates the entry of food into the stomach.
b) It controls the release of bile and pancreatic juices into the duodenum.
c) It facilitates absorption of nutrients in the ileum.
d) It regulates the entry of food into the small intestine from the common bile and common pancreatic duct.
e) It controls the passage of faeces from the rectum from the ampulla of vater.
Question 12:
Which taste receptors are primarily responsible for detecting a taste associated with savoury and meaty flavours?
a) Sweet receptors – T1R2+T1R3
b) Sour receptors – PKD2L1
c) Bitter receptors – T2R
d) Umami receptors – T1R1+T1R3
e) Salty receptors – ENAC
Question 13:
What is the role of the microbiota in the production and absorption of short-chain fatty acids (SCFAs) in the large intestine?
a) Microbiota break down carbohydrates into glucose for absorption.
b) Microbiota produce bile salts to aid in lipid digestion.
c) Microbiota synthesize vitamins A, D, E, and K for absorption.
d) Microbiota ferment dietary fibre to produce SCFAs, which are absorbed and used for energy.
e) Microbiota release enzymes that break down proteins into amino acids.
Question 14:
What is the primary function of the mucus-bicarbonate barrier in the gastrointestinal tract?
a) It acts as a selective filter allowing only specific nutrients to pass through to the epithelial cells for absorption.
b) It provides lubrication to facilitate the smooth passage of food through the gastrointestinal tract.
c) It serves as a medium for enzyme activation and enhances the efficiency of digestive processes.
d) It maintains an optimal pH environment to activate pepsinogen into pepsin for protein digestion.
e) It provides a protective layer that shields the gastrointestinal lining from acidic and enzymatic damage.
Question 15:
What is the primary function of the pyloric sphincter in the digestive system?
a) It prevents the backflow of acid into the oesophagus.
b) It controls the release of bile pancreatic juices into the duodenum.
c) It regulates the passage of chyme from the stomach to the duodenum.
d) It facilitates the absorption of nutrients in the small intestine by regulating food entry.
e) It secretes digestive enzymes into the stomach to aid in protein digestion.
Question 16:
Which of the following enzymes is responsible for digesting proteins in the stomach?
a) Intrinsic factor
b) Haptocorrin
c) Trypsin
d) Pepsin
e) Chymotrypsinogen
Question 17:
Which of the following best describes the primary function of the large intestine (colon) in digestion?
a) It produces vitamin K and facilitates the absorption of vitamin B12.
b) It synthesizes short-chain fatty acids (SCFAs) and converts primary bile acids into secondary bile acids.
c) It absorbs water and electrolytes to form stool and converts SCFAs into secondary bile acids.
d) It facilitates the absorption of water and electrolytes; forms stool, and the colon bacteria produce SCFAs from dietary fibre.
e) It converts primary bile acids into secondary bile acids, synthesizes vitamin B12, and regulates SCFA production.
Question 18:
What is the primary function of the gallbladder in the digestive process?
a) It produces bile salts to neutralize stomach acid before it enters the small intestine.
b) Emulsification of lipids.
c) It concentrates and stores bile produced by the liver, releasing it into the small intestine to aid in fat digestion.
d) Production of cholic acid and chenodeoxycholic acid.
e) It synthesizes digestive enzymes to break down fats into fatty acids.
Question 19:
Which hormone is primarily responsible for stimulating the release of bicarbonate into intestine during digestion?
a) CCK
b) VIP
c) Somatostatin
d) Secretin
e) PP
Question 20:
What is the primary role of the enteric nervous system (ENS) in the gastrointestinal (GI) tract, and how does it differ from the autonomic nervous system (ANS)?
a) It coordinates peristalsis and regulates blood flow within the GI tract, contrasting with the ANS’s role in hormone release.
b) It controls the release of digestive enzymes and hormones, differentiating from the ANS’s regulation of cardiac muscle contraction.
c) It manages GI motility and local secretion independently, unlike the ANS’s role in sensory perception.
d) It governs GI function, including motility and secretion, autonomously, contrasting with the ANS’s regulation of smooth muscle and glandular activity.
e) It moderates GI blood flow and mucosal immune responses, differentiating from the ANS’s regulation of skeletal muscle contraction.
Question 21:
In the gut, the release of gastrin plays a crucial role in digestion. What stimulates the release of gastrin, and what is its main function?
a) Gastrin release is stimulated by low stomach pH, and it promotes pancreatic enzyme secretion.
b) Gastrin release is stimulated by high stomach pH, and it enhances small intestine motility.
c) Gastrin release is stimulated by the presence of fatty acids, and it inhibits gastric acid production.
d) Gastrin release is stimulated by amino acids in the stomach, and it stimulates gastric acid secretion.
e) Gastrin release is stimulated by elevated blood glucose levels, and it activates bile release.
Question 22:
Which of the following vitamins is fat-soluble and primarily absorbed in the small intestine by forming micelles with dietary lipids?
a) Vitamin C (ascorbic acid)
b) Vitamin B6 (pyridoxine)
c) Vitamin D (cholecalciferol)
d) Folic Acid
e) Vitamin B12 (cobalamin)
Question 23:
Which phase of secretion involves the release of acid and pepsinogen?
a) Cephalic phase
b) Gastric phase
c) Intestinal phase
d) Fasting phase
e) Absorptive phase
Question 24:
In the context of gastrointestinal embryology, during which week of gestation does gut rotation occur?
a) Week 3
b) Week 6
c) Week 6
d) Week 12
e) Week 22
Question 25:
Which gastrointestinal hormone is responsible for stimulating the pancreas to release digestive enzymes and the gallbladder to contract and release bile into the duodenum?
a) Gastrin
b) Cholecystokinin (CCK)
c) Somatostatin
d) Secretin
e) VIP
Question 26:
Which part of the gastrointestinal tract is primarily responsible for the absorption of vitamin B12?
a) Duodenum
b) Jejunum
c) Ileum
d) Stomach
e) Colon
Question 27:
In the context of the gastrointestinal tract’s neural control, which plexus is responsible for coordinating and regulating the digestive movement within the walls of the GI tract itself?
a) Myenteric (Auerbach’s) plexus
b) Submucosal (Meissner’s) plexus
c) Celiac plexus
d) Hypogastric plexus
e) Sympathetic chain ganglia
Question 28:
Which gastrointestinal hormone is produced by D cells and acts to inhibit acid secretion in the stomach?
a) Gastrin
b) Cholecystokinin (CCK)
c) Somatostatin
d) Secretin
e) Ghrelin
Question 29:
During which phase of gastric secretion, in response to the ingestion of a meal, does the gastric mucosa release intrinsic factor, which is essential for the absorption of vitamin B12 in the ileum?
a) Cephalic phase
b) Gastric phase
c) Intestinal phase
d) Postprandial phase
e) Absorptive phase
Question 30:
In the context of gut-brain communication, what region of the brain plays a pivotal role in regulating appetite and satiety, often referred to as the “satiety centre”?
a) Hypothalamus
b) Amygdala
c) Hippocampus
d) Thalamus
e) Medulla oblongata
Question 31:
In the context of gut microbiota, what is the significance of the term “dysbiosis,” and how can it impact human health?
a) Dysbiosis refers to the absence of gut bacteria and is beneficial for health.
b) Dysbiosis indicates a healthy balance of gut microbes, promoting optimal digestion.
c) Dysbiosis is an imbalance in gut microbial communities, potentially leading to digestive disorders and inflammation.
d) Dysbiosis represents the diversity of gut bacteria, enhancing nutrient absorption.
e) Dysbiosis signifies a natural fluctuation in gut microbiota without health consequences.
Question 32:
In the context of liver function, what is the primary role of Kupffer cells?
a) Storage of glycogen
b) Synthesis of bile
c) Immune regulation
d) Storage of Vitamin A
e) Regulation of blood glucose levels
Question 33:
What is the primary function of stellate cells in the liver?
a) Synthesis of cholic acid and chenodeoxycholic acid
b) Storage of fat and vitamin A
c) Detoxification of drugs and toxins
d) Regulation of blood glucose levels
e) Production of albumin
Question 34:
Which anatomical structure is primarily responsible for attaching the small intestine to the posterior abdominal wall and facilitating its mobility for efficient digestion and absorption?
a) Mesocolon
b) Mesentery
c) Omentum
d) Peritoneum
e) Parietal peritoneum
Question 35:
During obesity, how is insulin sensitivity typically affected in adipocytes (fat cells)?
a) Insulin sensitivity increases in adipocytes
b) Insulin sensitivity remains unchanged in adipocytes
c) Insulin sensitivity decreases in adipocytes
d) Insulin sensitivity is not relevant to adipocytes
e) Insulin only has effect on muscle cells, not adipocytes
Answer: c) Insulin sensitivity decreases in adipocytes
Question 36:
Which vascular system carries nutrient-rich blood from the intestines to the liver for processing?
a) Systemic circulation
b) Pulmonary circulation
c) Portal circulation
d) Lymphatic circulation
e) Renal circulation
Question 37:
The greater omentum, a fatty apron-like structure, primarily attaches to which part of stomach?
a) Fundus of Stomach
b) Pylorus of Stomach
c) Cardia of Stomach
d) Greater Curvature of Stomach
e) Lesser Curvature of Stomach
Question 38:
Which cells in the pancreas are responsible for producing and secreting digestive enzymes into the small intestine?
a) Alpha cells
b) Beta cells
c) Acinar cells
d) Islet cells
e) Duct cells
Question 39:
Which liver enzyme is commonly used as a marker for hepatocellular damage and is elevated in conditions like hepatitis?
a) Alkaline phosphatase (ALP)
b) Albumin
c) Alanine aminotransferase (ALT)
d) Gamma-glutamyl transferase (GGT)
e) Prothrombin Time (PT)
Question 40:
Which process helps maintain the integrity of the gastrointestinal epithelium in response to injury?
a) Vomiting reflex
b) Treg and Trefoil peptides
c) Mucosal and bicarbonate secretion
d) Gastrin and hypovolaemia
e) Defecation
Question 41:
Which nutrient transporter is primarily responsible for the absorption of monosaccharides in the small intestine?
a) SGLT
b) Na+/K+ pump
c) GLUT 2
d) GLUT 4
e) GLUT 5
Question 42:
Which specialized cells found in Peyer’s patches play a crucial role in capturing and presenting antigens to immune cells, initiating an immune response in the gut?
a) Goblet cells
b) Paneth cells
c) M cells
d) IgA
e) P cells
Question 43:
In the context of secretory diarrhoea, what is the primary mechanism by which toxins like cholera toxin induce excessive secretion of water and electrolytes into the intestine?
a) Activation of CFTR channels
b) Inhibition of sodium-potassium ATPase
c) Activation of GPCR
d) Inhibition of aquaporins
e) Stimulation of paracellular and transcellular transport
Question 44:
Trypsinogen, the inactive precursor of trypsin, is initially secreted by which organ or gland in the digestive system to digest proteins?
a) Liver
b) Gallbladder
c) Stomach
d) Pancreas
e) Small intestine
Question 45:
Which water-soluble vitamin is primarily absorbed in the small intestine and plays a crucial role in collagen formation, wound healing, and as an antioxidant?
a) Vitamin A
b) Vitamin C
c) Vitamin D
d) Vitamin E
e) Vitamin K
Question 46:
The submucosal plexus, also known as Meissner’s plexus, is a critical component of the enteric nervous system (ENS). What is the primary function of the submucosal plexus within the gastrointestinal tract?
a) Regulation of smooth muscle contraction for peristalsis
b) Secretion of digestive enzymes and gastric juices
c) Coordination of voluntary muscle movements in the gut
d) Control of blood flow to the gastrointestinal mucosa
e) Detection and response to luminal contents and reflexes in the mucosa
Question 47:
Which of the following accurately distinguishes the primary functions of Meissner’s plexus (submucosal plexus) from those of Myenteric plexus (Auerbach’s plexus) within the gastrointestinal tract?
a) Meissner’s plexus regulates blood flow, while Myenteric plexus controls secretion.
b) Meissner’s plexus primarily controls motility, while Myenteric plexus is responsible for sensory perception.
c) Meissner’s plexus is involved in secretion and absorption, whereas Myenteric plexus mainly coordinates muscle contractions and motility.
d) Meissner’s plexus modulates immune responses, while Myenteric plexus regulates glandular secretions.
e) Meissner’s plexus initiates reflexes, while Myenteric plexus is responsible for nutrient sensing.
Question 48:
Elevated levels of bilirubin, alkaline phosphatase (ALP), and gamma-glutamyl transferase (GGT) in liver function tests (LFTs) can result from various causes. Which of the following represents an abnormal combination of these markers in LFTs?
a) Haemolysis
b) Hyperthyroidism
c) Hepatic steatosis
d) Hepatitis A infection
e) Cholestasis
Question 49:
In liver function tests (LFTs), which of the following statements best explains the role of albumin as a marker?
a) Albumin is a marker for hepatocellular injury.
b) Albumin is a marker for clotting functions.
c) Albumin is a marker for bile duct obstruction.
d) Albumin is a marker for synthetic function, as it is primarily synthesized by the liver.
e) All of the above
Question 50:
Which of the following is a potential consequence of hypermotility?
a) Delayed gastric emptying
b) Excessive nutrient absorption
c) Constipation
d) Excessive bile secretion
e) Diarrhoea
Question 51:
Prostaglandins are lipid compounds that play various roles in the gastrointestinal (GI) tract. In the context of the GI mucosa, what is one of the primary functions of prostaglandins?
a) Inhibition of mucus production
b) Suppression of immune responses
c) Reduction in gastric acid secretion
d) Promotion of blood flow to the GI mucosa
e) Enhancement of bile secretion
Question 52:
The polymeric immunoglobulin receptor (pIgR) plays a crucial role in mucosal immunity by transporting a specific immunoglobulin across the mucosa. Which immunoglobulin is primarily transported and secreted in mucosal surfaces via pIgR?
a) Immunoglobulin A (IgA)
b) Immunoglobulin G (IgG)
c) Immunoglobulin M (IgM)
d) Immunoglobulin D (IgD)
e) Immunoglobulin E (IgE)
Question 53:
Mastication, the process of chewing food, is under the control of specific nerves that innervate the muscles involved. Which of the following nerves is primarily responsible for motor control during mastication?
a) Vagus nerve (cranial nerve X)
b) Glossopharyngeal nerve (cranial nerve IX)
c) Trigeminal nerve (cranial nerve V)
d) Hypoglossal nerve (cranial nerve XII)
e) Accessory nerve (cranial nerve XI)
Question 54:
Salivary glands play a crucial role in the initial stages of digestion. Which cranial nerve innervates the parotid gland, and which cranial nerve innervates both the sublingual and submandibular glands based on the primary innervation patterns?
a) Parotid gland – Innervated by the trigeminal nerve (cranial nerve V); Sublingual and Submandibular glands – Innervated by the glossopharyngeal nerve (cranial nerve IX)
b) Parotid gland – Innervated by the glossopharyngeal nerve (cranial nerve IX); Sublingual and Submandibular glands – Innervated by the facial nerve (cranial nerve VII)
c) Parotid gland – Innervated by the vagus nerve (cranial nerve X); Sublingual and Submandibular glands – Innervated by the trigeminal nerve (cranial nerve V)
d) Parotid gland – Innervated by the facial nerve (cranial nerve VII); Sublingual and Submandibular glands – Innervated by the vagus nerve (cranial nerve X)
e) Parotid gland – Innervated by the hypoglossal nerve (cranial nerve XII); Sublingual and Submandibular glands – Innervated by the accessory nerve (cranial nerve XI)
Question 55:
In the context of salivary gland innervation, what is the typical effect of sympathetic innervation on saliva composition?
a) Sympathetic innervation stimulates the secretion of watery, enzyme-rich saliva.
b) Sympathetic innervation has no effect on saliva composition.
c) Sympathetic innervation stimulates the secretion of protein-rich saliva.
d) Sympathetic innervation selectively enhances specific saliva components.
e) Sympathetic innervation varies in its effect on saliva composition depending on the type of gland.
Question 56:
The interstitial cells of Cajal (ICC) are specialized cells found in the gastrointestinal tract. What is the primary role of ICC in the gastrointestinal system?
a) ICC regulate the absorption of nutrients in the small intestine by modulating villus motility.
b) ICC generate and propagate electrical slow waves that coordinate smooth muscle contractions.
c) ICC act as sensory receptors for detecting mechanical changes in the gastrointestinal tract.
d) ICC secrete digestive enzymes to facilitate the breakdown of food in the stomach and intestines.
e) ICC mediate immune responses and protect the gastrointestinal lining from pathogens.
Question 57:
Tongue movement is essential for tasks like speech and swallowing. Which cranial nerve is primarily responsible for controlling the voluntary movement of the tongue’s intrinsic and extrinsic muscles?
a) Trigeminal nerve (cranial nerve V)
b) Facial nerve (cranial nerve VII)
c) Glossopharyngeal nerve (cranial nerve IX)
d) Hypoglossal nerve (cranial nerve XII)
e) Vagus nerve (cranial nerve X)
Question 58:
Fructose, a monosaccharide found in various fruits and honey, is absorbed in the small intestine through a specific glucose transporter protein. What is the name of the transporter responsible for the facilitated diffusion of fructose into enterocytes?
a) GLUT1
b) GLUT2
c) GLUT3
d) GLUT4
e) GLUT5
Question 59:
Gastrin is a hormone produced by certain cells in the stomach. Apart from its well-known role in stimulating gastric acid secretion, gastrin also plays a vital role in the repair and maintenance of the gastrointestinal (GI) tract. How does gastrin contribute to the repair and maintenance of the GI mucosa?
a) Gastrin stimulates gastric acid release
b) Gastrin inhibits the production of bicarbonate (HCO3-).
c) Gastrin stimulates cell proliferation and mucosal growth.
d) Gastrin decreases blood flow to the GI mucosa.
e) Gastrin activates enzymes that digest the mucosal lining.
Question 60:
In the large intestine, particularly the colon, how many layers of mucus are typically present, contributing to its functions in protection and stool movement?
a) One layer of mucus
b) Two layers of mucus
c) Three layers of mucus
d) Four layers of mucus
e) One discontinuous layer of mucus
Question 61:
A diet rich in fruits and legumes is known for its positive effects on gut health. What is a likely outcome of consuming a high fruit and legume fibre diet?
a) Decreased production of short-chain fatty acids (SCFA) and gram-positive bacteria
b) Higher risk of pathogenic gram-positive bacteria colonization
c) Improved establishment of harmful gut microbes such as gram-negative bacteria
d) Increased levels of SCFA and gram-positive bacteria
e) Enhanced digestion of animal proteins and more gram-negative bacteria
Question 62:
Short-chain fatty acids (SCFAs) have been found to influence insulin sensitivity in various tissues. What is the typical impact of SCFAs on muscle insulin sensitivity?
a) SCFAs decrease insulin sensitivity in muscle.
b) SCFAs have no effect on insulin sensitivity in muscle.
c) SCFAs increase insulin sensitivity in muscle.
d) SCFAs decrease insulin sensitivity in liver but not in muscle.
e) SCFAs increase insulin sensitivity in liver but not in muscle.
Question 63:
Incretins are gastrointestinal hormones that play a crucial role in glucose regulation. Which of the following statements accurately describes the actions of incretins like GIP (glucose-dependent insulinotropic peptide) and GLP-1 (glucagon-like peptide-1)?
a) Incretins decrease insulin release from the pancreas.
b) Incretins primarily act on the liver to release glucose into the bloodstream.
c) Incretins stimulate insulin secretion and inhibit glucagon release from the pancreas.
d) Incretins have no effect on blood glucose levels.
e) Incretins inhibit the absorption of nutrients in the small intestine.
Question 64:
Motilin, a gastrointestinal hormone, is known for its role in fasting and its function in clearing out residue from the gastrointestinal (GI) tract. During fasting, what is the primary action of motilin?
a) Motilin promotes the release of digestive enzymes from the pancreas.
b) Motilin stimulates the secretion of hydrochloric acid in the stomach.
c) Motilin inhibits smooth muscle contractions in the GI tract.
d) Motilin enhances GI motility and clears residual material from the gut.
e) Motilin decreases blood flow to the GI mucosa.
Question 65:
The migrating myoelectric complex (MMC) is a cyclic pattern of electrical and muscular activity that occurs in the gastrointestinal (GI) tract during fasting. What is the primary function of the MMC?
a) MMC promotes the secretion of bile and pancreatic juice in response to food intake.
b) MMC facilitates the absorption of nutrients in the small intestine.
c) MMC triggers the release of gastric acid in the stomach to aid digestion.
d) MMC moves undigested food and bacteria from the stomach and small intestine to the colon during fasting.
e) MMC enhances the relaxation of the lower oesophageal sphincter to allow food entry into the stomach.
Question 66:
In the gastrointestinal (GI) tract, what is located within the tissue layer between the circular and longitudinal muscle layers?
a) Submucosal plexus
b) Mucosal layer
c) Meissner’s plexus
d) Serosa
e) Myenteric plexus
Question 67:
Which one contains specialized oblique muscles within its muscular layers, contributing to twisting and squeezing motions for digestion?
a) Stomach
b) Small intestine
c) Large intestine
d) Oesophagus
e) Abdominal
Question 68:
The vago-vagal reflex is an important aspect of communication between the gastrointestinal (GI) tract and the brain. What best describes the vago-vagal reflex?
a) It is a sensory pathway from the brain to the gut that regulates appetite.
b) It involves the sympathetic nervous system in regulating gut motility.
c) It is a feedback loop that includes both afferent and efferent branches of the vagus nerve, aiding in GI regulation.
d) It primarily controls defecation reflex.
e) It is responsible for the release of digestive enzymes in response to food ingestion.
Question 69:
Chylomicrons are lipoprotein particles involved in the transport of dietary lipids. What is the primary role of chylomicrons in the body?
a) Chylomicrons store excess glucose in the liver.
b) Chylomicrons facilitate the absorption of water-soluble vitamins.
c) Chylomicrons transport dietary lipids, such as triglycerides, from the small intestine to peripheral tissues.
d) Chylomicrons secrete digestive enzymes in the stomach.
e) Chylomicrons regulate blood glucose levels.
Question 70:
In the context of abdominal anatomy, where are the hypochondriac regions located?
a) They are situated in the upper-left quadrant of the abdomen.
b) They are found in the upper-right quadrant of the abdomen.
c) They are in the lower-left quadrant of the abdomen.
d) They are positioned in the lower-right quadrant of the abdomen.
e) They are in the upper lateral parts of the abdomen, on either side of the epigastric region.
Question 71:
Which of the following statements regarding peristalsis in the oesophagus is correct?
a) Peristalsis in the oesophagus is under voluntary control.
b) Peristalsis is the contraction of antagonistic muscles in the digestive system.
c) Peristalsis in the oesophagus involves simultaneous contraction of circular and longitudinal muscle layers.
d) Peristalsis in the oesophagus occurs only in the upper third of the oesophagus.
e) Peristalsis in the oesophagus is mediated by cranial nerves V and VII.
Question 72:
What is the anatomical significance of the term “porta hepatis” in relation to the liver?
a) Porta hepatis refers to the primary blood supply to the liver.
b) Porta hepatis indicates the location of the gallbladder within the liver.
c) Porta hepatis denotes the site where the hepatic artery, portal vein, and common bile duct enter and exit the liver.
d) Porta hepatis refers to the inflammation of the hepatic portal vein.
e) Porta hepatis describes the outer protective covering of the liver.
Question 73:
What is located at the central region of a liver lobule and represents the central vein that collects blood from hepatic sinusoids, eventually merging into larger hepatic veins for blood drainage from the liver?
a) Central lymph
b) Kupffer cells
c) Central artery
d) Central Bile canaliculi
e) Central vein
Question 74:
Bile, produced by the liver and stored in the gallbladder, plays a crucial role in the digestion and absorption of various nutrients. Which of the following vitamins is primarily dependent on bile for its digestion and absorption in the small intestine?
a) Vitamin A
b) Vitamin B3
c) Vitamin B6
d) Vitamin B12
e) Vitamin C
Question 75:
In the human body, where is bile primarily produced as a crucial digestive fluid?
a) In the pancreas
b) In the stomach
c) In the small intestine
d) In the liver
e) In the gallbladder
Question 76:
Which type of cells in the liver are primarily responsible for the production of bile?
a) Hepatocytes
b) Acinar cells
c) Stellate cells
d) Kupffer cells
e) Mucous cells
Question 77:
Which structure connects the gallbladder to the common bile duct, facilitating the storage and controlled release of bile for digestion?
a) Cystic duct
b) Pancreatic duct
c) Duodenal duct
d) Hepatic duct
e) Jejunal duct
Question 78:
Tinea coli, often referred to as the “taenia coli,” is a notable anatomical feature of the colon. What is the primary role or function of the tinea coli?
a) Tinea coli is involved in the absorption of water and electrolytes.
b) Tinea coli assists in the mixing and propulsion of faecal material.
c) Tinea coli is responsible for the synthesis of digestive enzymes.
d) Tinea coli serves as a protective barrier against pathogens.
e) Tinea coli regulates the release of bile into the colon.
Question 79:
The liver, pancreas, and gall bladder are vital digestive organs that play a crucial role in the process of digestion. Why do these organs empty their secretions into the duodenum?
a) Due to the presence of specialized enzymes in the duodenal mucosa.
b) To regulate the pH of the duodenal contents.
c) Because diverticula bud grows from the duodenum during embryonic development.
d) To initiate the absorption of nutrients in the jejunum.
e) As a response to hormonal signals from the ileum.
Question 80:
During embryonic development, the midgut undergoes a complex series of rotations as it herniates into the umbilical cord and subsequently returns to the abdominal cavity. What angle of rotation does the midgut undergo during herniation and around which axis does this rotation occur?
a) 90 degrees around the superior mesenteric artery.
b) 270 degrees around the inferior mesenteric artery.
c) 270 degrees around the superior mesenteric artery.
d) 90 degrees around the celiac artery.
e) 270 degrees around the portal vein.
Question 81:
The external anal sphincter is a vital muscle for maintaining faecal continence. Which nerve provides voluntary control over the external anal sphincter, and from which spinal cord segments does this nerve originate?
a) Pelvic splanchnic nerves; S2-S4
b) Superior rectal nerve; L1-L2
c) Pudendal nerve; S2-S4
d) Sacral splanchnic nerves; S1-S3
e) Coccygeal nerve; Co1-Co2
Question 82:
The process of closing the jaw during mastication and biting is primarily achieved by which of the following muscles?
a) Digastric muscle
b) Masseter muscle
c) Lateral pterygoid muscle
d) Sternocleidomastoid muscle
e) Trapezius muscle
Question 83:
Saliva plays a crucial role in protecting teeth. How does saliva achieve this protective function?
a) Saliva neutralizes acids by increasing their pH.
b) Saliva forms a physical barrier on tooth surfaces.
c) Saliva provides a source of calcium and phosphate ions.
d) Saliva inhibits the growth of acid-producing bacteria.
e) Saliva promotes enamel hardening through fluoride release.
Question 84:
During embryonic development, the foregut gives rise to which of the following structures?
a) Stomach and upper duodenum
b) Small intestine and cecum
c) Colon and rectum
d) Lower duodenum and jejunum
e) Ascending colon and appendix
Question 85:
The midgut forms which of the following structures during embryonic development?
a) Liver and gallbladder
b) Descending colon and sigmoid colon
c) Cecum, appendix, and ascending colon
d) Spleen and pancreas
e) Rectum and anal canal
Question 86:
During embryonic development, the hindgut gives rise to which of the following structures?
a) Liver and gallbladder
b) Small intestine and cecum
c) Stomach and upper duodenum
d) Descending colon and sigmoid colon
e) Kidneys and ureters
Question 87:
The Superior Mesenteric Artery (SMA) is a major abdominal artery that supplies various organs. Which of the following structures is primarily supplied by the SMA?
a) Stomach and spleen
b) Liver and gallbladder
c) Small intestine and ascending colon
d) Kidneys and adrenal glands
e) Pancreas and duodenum
Question 88:
The Coeliac Trunk, a major abdominal artery, typically branches into which of the following arteries?
a) Superior mesenteric artery, renal artery, and left gastric artery
b) Left gastric artery, common hepatic artery and splenic artery
c) Right renal artery, common hepatic artery, and left gastroepiploic artery
d) Internal iliac artery, gastroduodenal artery, and inferior mesenteric artery
e) Right gastric artery, colic artery, and inferior pancreaticoduodenal artery
Question 89:
Portosystemic anastomoses are important connections between the portal venous system and the systemic venous system. One significant site of portosystemic anastomosis is found in the:
a) Small intestine
b) Liver
c) Spleen
d) Oesophagus
e) Pancreas
Question 90:
Which structure serves as a temporary storage reservoir for lymph in the abdomen, allowing it to collect and transport lymph from the lower body and intestines before eventually draining into the thoracic duct?
a) Cystic duct
b) Hepatic duct
c) Mesenteric duct
d) Jugular duct
e) Cisterna chyli
Question 91:
In the gastrointestinal (GI) tract, nitric oxide (NO) and vasoactive intestinal peptide (VIP) play a significant role. What is their primary effect on smooth muscle in the GI tract?
a) They stimulate smooth muscle contraction.
b) They have no effect on smooth muscle.
c) They promote smooth muscle relaxation.
d) They induce smooth muscle hypertrophy.
e) They enhance smooth muscle peristalsis.
Question 92:
The stomach is divided into several regions, each with distinct functions. Which part of the stomach is primarily responsible for the secretion of gastric acid?
a) Pylorus
b) Fundus
c) Antrum
d) Corpus
e) Cardia
Question 93:
Cholecystokinin (CCK) is a gastrointestinal hormone that plays a vital role in digestion. When is CCK primarily released?
a) When carbohydrates are detected in the small intestine.
b) When the stomach is empty.
c) When dietary fibre is consumed.
d) When fats and proteins are detected in the small intestine.
e) When the colon is actively digesting food.
Question 94:
Histamine is a signalling molecule found in various tissues, including the gastrointestinal (GI) tract. In the GI system, histamine primarily acts as a:
a) Vasodilator
b) Vasoconstrictor
c) Inhibitor of acid secretion
d) Stimulator of acid secretion
e) Muscle relaxant
Question 95:
Gastrin, a key hormone in regulating gastric acid secretion, exerts its effects by binding to specific receptors. In the stomach, gastrin primarily interacts with:
a) CCK-2 receptors on parietal cells to stimulate acid secretion
b) H2 receptors on chief cells to inhibit pepsinogen secretion
c) CCK-2 receptors on ECL cells to produce histamine
d) M3 receptors on parietal cells to inhibit acid secretion
e) D2 receptors on chief cells to stimulate pepsinogen secretion
Question 96:
Proton pump inhibitors (PPIs) are commonly prescribed to manage conditions related to excessive gastric acid secretion. How do PPIs help in reducing gastric acid levels?
a) They suppress the activity of the proton pump on G cells.
b) They suppress the activity of the proton pump on D cells.
c) They suppress the activity of the proton pump on ECL cells.
d) They suppress the activity of the proton pump on parietal cells.
e) They suppress the activity of the proton pump on chief cells.
Question 97:
Ghrelin is a hormone known for its role in regulating appetite and hunger. How does ghrelin inhibit the vagal afferent response to food intake?
a) Ghrelin stimulates the release of cholecystokinin (CCK), which inhibits vagal afferent activity.
b) Ghrelin suppresses the release of gastrin, reducing vagal afferent activation.
c) Ghrelin directly inhibits the firing of vagal afferent nerves.
d) Ghrelin increases the release of leptin, which counteracts vagal afferent signals.
e) Ghrelin has no direct effect on vagal afferent response.
Question 98:
Splanchnic nerves are a vital part of the autonomic nervous system, responsible for innervating various abdominal organs. Which of the following statements regarding splanchnic nerves is accurate?
a) Splanchnic nerves carry sensory information from abdominal organs to the central nervous system.
b) Splanchnic nerves contain both sympathetic and parasympathetic fibres, regulating visceral functions.
c) Splanchnic nerves directly innervate skeletal muscles in the abdominal wall.
d) Splanchnic nerves primarily regulate conscious motor functions in the digestive system.
e) Splanchnic nerves are exclusively associated with the somatic nervous system.
Question 99:
GLP-1 (glucagon-like peptide-1) plays a significant role in glucose homeostasis and appetite regulation. Which of the following best represents the actions of GLP-1?
a) GLP-1 stimulates the secretion of glucagon from pancreatic alpha cells.
b) GLP-1 promotes glycogen breakdown in the liver.
c) GLP-1 triggers insulin secretion from pancreatic beta cells and inhibits food intake.
d) GLP-1 enhances the absorption of dietary fats in the small intestine.
e) GLP-1 directly acts on skeletal muscle to promote glucose uptake.
Question 100:
The liver is composed of various cell types, each with specific functions. Among the following options, which one represents a parenchymal cell in the liver?
a) Kupffer cell
b) Stellate cell
c) Hepatocyte
d) Endothelial cell
e) Peritoneum
Question 101:
The colour of stool can vary, and it is influenced by several factors. What substance primarily contributes to the brown colour of normal stool?
a) Bilirubin
b) Urobilinogen
c) Stercobilin
d) Melanin
e) Cholecystokinin
Question 102:
What specific type of molecules forms the core of micelles and encapsulates for efficient absorption?
a) 5-alpha reductase
b) Triglycerides
c) Bile salts
d) Chylomicrons
e) Fatty acids
Question 104:
The process by which bile acids are absorbed in the ileum, transported to the liver via the portal vein, and then secreted into bile is known as:
a) Hepatic recycling
b) Biliary reabsorption
c) Enterohepatic circulation
d) Ileal resynthesis
e) Cholestatic transport
Question 105:
Jaundice, a yellowing of the skin and eyes, is primarily caused by the excess accumulation of which pigment in the body?
a) Melanin
b) Haemoglobin
c) Bilirubin
d) Carotene
e) Urea
Question 106:
Lactose, a disaccharide found in dairy products, is enzymatically broken down into which two monosaccharides during the process of digestion?
a) Glucose and galactose
b) Fructose and glucose
c) Sucrose and maltose
d) Glucose and lactase
e) Galactose and sucrose
Question 107:
Oral rehydration tablets are commonly used to combat dehydration, especially in cases of diarrhoea. What are the two key components found in these tablets that help restore electrolyte balance and facilitate fluid absorption?
a) Fructose and potassium
b) Iron and magnesium
c) Sodium and Calcium
d) Phosphate and chloride
e) Sodium and glucose
Question 107:
Trypsin is a digestive enzyme that plays a crucial role in protein digestion. What is the optimal pH range at which trypsin exhibits its maximum enzymatic activity within the human digestive system?
a) pH 2-3
b) pH 5-6
c) pH 7-9
d) pH 10-11
e) pH 12-13
Question 108:
Among the fat-soluble vitamins, which one is NOT passively transported across the intestinal membrane and instead requires specific transport mechanisms for absorption?
a) Vitamin A
b) Vitamin D
c) Vitamin E
d) Vitamin K
e) Vitamin C
Question 109:
Vitamin A plays a crucial role in various physiological processes. Which of the following functions is primarily associated with the importance of vitamin A?
a) Blood clotting and wound healing
b) Antioxidant defence and immune support
c) Maintenance of healthy skin and vision
d) Muscle contraction and nerve transmission
e) Absorption of calcium and phosphate
Question 110:
Iron is an essential mineral for various physiological processes, including oxygen transport in the blood. Where in the gastrointestinal tract does most of the iron absorption occur?
a) Stomach
b) Duodenum
c) Jejunum
d) Ileum
e) Colon
Question 111:
In the process of nutrient absorption in the gastrointestinal tract, some substances are transported through the tight junctions between adjacent epithelial cells. What is this mode of transport called?
a) Transcellular transport
b) Intracellular transport
c) Paracellular transport
d) Active transport
e) Facilitated transport
Question 112:
Which of the following occurs due to increased gut motility?
a) Enhanced nutrient absorption
b) Slower transit time of food
c) Reduced mixing of digestive enzymes with food
d) Decreased risk of diarrhoea
e) Increased water absorption in the colon
Question 113:
Intestinal secretion, the process of releasing fluids into the intestinal lumen, serves various functions in the digestive system. Which of the following is a primary reason for intestinal secretion?
a) To dilute hypertonic solutions in the lumen
b) To absorb water from the large intestine
c) To aid in the mechanical breakdown of food
d) To activate digestive enzymes in the pancreas
e) None of the above
Question 114:
In the enteric nervous system, acetylcholine (Ach) serves as a crucial neurotransmitter. Which type of receptor family does Ach primarily bind to when mediating its effects in the gastrointestinal tract?
a) G protein-coupled receptors (GPCR)
b) Tyrosine kinase receptors
c) Nuclear receptors
d) Histidine receptors
e) Toll-like receptors
Question 115:
Cholera toxin is responsible for the severe diarrhoea seen in cholera infection. What is the primary mechanism by which cholera toxin increases the secretion of chloride ions (Cl-) into the intestinal lumen, leading to watery diarrhoea?
a) Activation of adenylate cyclase
b) Inhibition of sodium-potassium pump
c) Blockade of calcium channels
d) Stimulation of GABA receptors
e) Inhibition of voltage-gated potassium channels
Question 116:
Histamine receptor blockers, such as ranitidine (Zantac) work by blocking H2 histamine receptors can have various effects on physiological processes. Which of the following outcomes is a common effect of medications that block H2 histamine receptors in the GI system?
a) Increased gastric acid secretion
b) Bradycardia
c) Gastrointestinal bleeding
d) Sedation and drowsiness
e) Decreased gastric acid secretion
Question 117:
Prostaglandins, acetylcholine (Ach), gastrin, and histamine play crucial roles in gastrointestinal regulation. What common function do these molecules share when it comes to the gastrointestinal system?
a) They all enhance the absorption of nutrients in the small intestine.
b) They are all involved in the modulation of gastric acid secretion.
c) They inhibit the release of pancreatic enzymes.
d) They all serve as primary signalling molecules for initiating peristalsis.
e) They are essential for the regulation of bile secretion.
Question 118:
What is the primary neurotransmitter responsible for initiating peristalsis in the oesophagus during the oral phase of swallowing?
A) Acetylcholine
B) Serotonin
C) Dopamine
D) Norepinephrine
E) GABA
Question 119:
During the pharyngeal phase of swallowing, which structure prevents food from entering the trachea?
A) Epiglottis
B) Thyroid gland
C) Cricoid cartilage
D) Hyoid bone
E) Vocal cords
Question 120:
Which hormone is primarily responsible for initiating the migrating motor complex (MMC) in the fasting state of the intestinal tract?
A) Insulin
B) Glucagon
C) Cholecystokinin (CCK)
D) Motilin
E) Leptin
Question 121:
What is the main function of haustrations in the large intestine?
A) Mixing and churning of food
B) Absorption of nutrients
C) Propelling chyme
D) Propelling faecal material
E) Formation of faecal pellets
Question 122:
Which component of the gastrointestinal tract is responsible for voluntary control over defecation?
A) Small intestine
B) Large intestine
C) Ano-rectum
D) Duodenum
E) Cecum
Question 123:
Which neurotransmitter plays a key role in relaxing the lower oesophageal sphincter (LES) to allow food to enter the stomach during the swallowing process?
A) Serotonin
B) Nitric oxide
C) Epinephrine
D) Glutamate
E) Substance P
Question 124:
In the fasted state, what is the primary function of the small intestine’s migrating motor complex (MMC)?
A) Mixing chyme with digestive enzymes
B) Promoting nutrient absorption
C) Clearing undigested material
D) Initiating segmentation contractions
E) Storing bile for fat digestion
Question 125:
Which of the following is a characteristic of mass movements in the large intestine?
A) Slow, rhythmic contractions
B) Continuous mixing of chyme
C) Propelling faecal material over long distances
D) Occurring only in the ascending colon
E) Inhibited by sympathetic stimulation
Question 126:
Which anatomical structure acts as a reservoir for faeces and allows for the storage of stool until defecation?
A) Cecum
B) Duodenum
C) Ano-rectum
D) Ileum
E) Sigmoid colon
Question 127:
What is the primary function of the external anal sphincter in defecation?
A) Initiating peristalsis
B) Preventing reflux of stomach contents
C) Relaxing to allow the passage of stool
D) Regulating the release of digestive enzymes
E) Constricting the rectum for storage
Question 128:
Which of the following best characterizes the motility of the proximal stomach?
A) Receptive relaxation for efficient food intake
B) Gastric accommodation for storage of chyme
C) Propulsion of partially digested food
D) Grinding and retropulsion for further digestion
E) Reservoir function for prolonged digestion
Question 129:
Which component of gastric secretions is essential for the absorption of vitamin B12 in the ileum?
A) Pepsinogen
B) Gastric acid (HCl)
C) Intrinsic factor
D) Proteins
E) Haptocorrin (R-factor)
Question 130:
Which cell type in the gastric mucosa is primarily responsible for secreting gastric acid?
A) Chief cells
B) Parietal cells
C) Mucous neck cells
D) G cells
E) D cells
Question 131:
Which phase of gastric secretion is characterized by the release of gastrin, stimulating gastric acid production in response to partially digested food entering the stomach?
A) Cephalic phase
B) Gastric phase
C) Intestinal phase
D) Pyloric phase
E) Enteric phase
Question 132:
Hyper-acid secretion in the stomach is often associated with which condition, exacerbated by Helicobacter pylori infection?
A) Gastric ulcers
B) Gallstones
C) Crohn’s disease
D) Pancreatitis
E) Celiac disease
Question 133:
Which phase of gastric secretion primarily involves the release of secretin and cholecystokinin (CCK) to inhibit gastric acid secretion and promote pancreatic enzyme secretion?
A) Cephalic phase
B) Gastric phase
C) Intestinal phase
D) Pyloric phase
E) Enteric phase
Question 134:
Which component of gastric secretions is responsible for breaking down dietary triglycerides into fatty acids and glycerol?
A) Pepsinogen
B) Gastric acid (HCl)
C) Intrinsic factor
D) Mucus
E) Gastric lipases
Question 135:
Which cellular mechanism in gastric acid secretion involves the exchange of bicarbonate ions for chloride ions in the parietal cells?
A) Proton pump activation
B) Hydrochloric acid production
C) Acid secretion regulation
D) Bicarbonate secretion
E) Acidic protease release
Question 136:
Which phase of gastric secretion is initiated by the sight, smell, or taste of food and involves vagal stimulation leading to the release of gastrin?
A) Cephalic phase
B) Gastric phase
C) Intestinal phase
D) Pyloric phase
E) Enteric phase
Question 137:
In the context of hyper-acid secretion, what is the primary role of Helicobacter pylori in gastric disease?
A) Stimulating mucus production
B) Inhibiting gastric acid secretion
C) Protecting the stomach lining
D) Disrupting the gastric mucosal barrier
E) Promoting gastric accommodation
Question 139:
Where is bile primarily stored before release into the duodenum?
A) Liver
B) Stomach
C) Pancreas
D) Gallbladder
E) Spleen
Question 140:
What hormone stimulates gallbladder contraction and the relaxation of the sphincter of Oddi?
A) Insulin
B) Gastrin
C) Secretin
D) Cholecystokinin (CCK)
E) Glucagon
Question 141:
What is the primary function of the enterohepatic circulation of bile salts?
A) Neutralizing stomach acid
B) Enhancing protein digestion
C) Recycling bile salts for reuse
D) Promoting lipid absorption
E) Regulating glucose metabolism
Question 142:
How do bile salts aid in solubilizing products of lipid digestion in mixed micelles?
A) By breaking down triglycerides into free fatty acids
B) By emulsifying large fat droplets into smaller ones
C) By forming a hydrophilic shell around lipid particles
D) By converting lipids into water-soluble molecules
E) By inhibiting lipid digestion in the small intestine
Question 143:
What is one of the basic causes of jaundice?
A) Excessive water intake
B) Hyperactive gallbladder
C) Altered bilirubin metabolism
D) Overproduction of bile salts
E) Increased cholecystokinin secretion
Question 144:
When the mucosal barrier fails to protect the gut, what can be a consequence?
A) Enhanced nutrient absorption
B) Reduced acid secretion
C) Bacterial overgrowth
D) Improved digestion
E) Increased mucus production
Question 145:
Which component of the mucosal barrier is responsible for producing a thick, viscous layer that protects the epithelial cells from acid and digestive enzymes in the stomach?
A) Prostaglandins
B) Hydrochloric acid
C) Mucus-bicarbonate layer
D) Gastrin
E) Pepsin
Question 146:
What is the primary role of prostaglandins in the gastrointestinal tract?
A) Enhancing nutrient absorption
B) Promoting gastric acid secretion
C) Stimulating immune cell activity
D) Regulating inflammatory responses
E) Inhibiting mucus production
Question 147:
When the gastrointestinal epithelium experiences insult that leads to injury, what is the initial response?
A) Enhanced nutrient absorption
B) Proliferation of epithelial cells
C) Apoptosis (programmed cell death)
D) Decreased cell migration
E) Increased mucus secretion
Question 148:
Which process involves the replacement of injured or lost gastrointestinal epithelial cells by adjacent healthy cells to restore the integrity of the mucosal barrier?
A) Apoptosis
B) Inflammation
C) Restitution
D) Digestion
E) Fibrosis
Which type of liver cells are primarily responsible for the synthesis of proteins, including albumin and clotting factors?
A) Hepatocytes
B) Kupffer cells
C) Stellate (Ito) cells
D) Endothelial cells
E) Biliary epithelial cells
Question 150:
Which type of liver cells are specialized macrophages responsible for phagocytosing pathogens and debris in the liver sinusoids?
A) Hepatocytes
B) Kupffer cells
C) Stellate (Ito) cells
D) Endothelial cells
E) Biliary epithelial cells
Question 151:
Which type of liver cells are responsible for storing vitamin A and can become activated in liver fibrosis and cirrhosis?
A) Hepatocytes
B) Kupffer cells
C) Stellate (Ito) cells
D) Endothelial cells
E) Biliary epithelial cells
Question 152:
What is the main function of the liver related to the synthesis of proteins?
A) Carbohydrate metabolism
B) Storage of fat-soluble vitamins
C) Detoxification of drugs
D) Synthesis of plasma proteins
E) Regulation of blood pressure
Question 153:
Which liver enzyme is primarily responsible for the metabolism of alcohol, converting it into acetaldehyde?
A) Amylase
B) Lipase
C) Aldehyde dehydrogenase
D) Cytochrome P450 2E1 (CYP2E1)
E) Glutamine synthetase
Question 154:
Which of the following bile acids is considered a primary bile acid synthesised in the liver?
A. Deoxycholic acid
B. Lithocholic acid
C. Chenodeoxycholic acid
D. Glycine
E. Taurine
Question 155:
Which enzyme is responsible for the conjugation of bilirubin in the liver?
A. Lipase
B. Glucuronyl transferase
C. Amylase
D. Pepsin
E. Lactase
Question 156:
Which of the following is a direct precursor of the secondary bile acid deoxycholic acid?
A. Cholic acid
B. Chenodeoxycholic acid
C. Ursodeoxycholic acid
D. Lithocholic acid
E. Taurocholic acid
Question 157:
Which of the following is NOT a function of bile acids in the digestive system?
A. Emulsification of dietary fats
B. Facilitation of fat-soluble vitamin absorption
C. Neutralisation of stomach acid
D. Elimination of cholesterol from the body
E. Activation of pancreatic lipase
Question 158:
Which of the following steps is NOT involved in enterohepatic circulation of bile acids?
A. Synthesis in the liver
B. Storage in the gallbladder
C. Secretion into the duodenum
D. Reabsorption in the colon
E. Transport back to the liver via the portal vein
Question 159:
Which of the following is the primary organ responsible for converting Vitamin D to its active form?
A. Liver
B. Kidney
C. Skin
D. Intestine
E. Pancreas
Question 160:
Which of the following compounds is a secondary bile acid formed from via the action of bacteria on the primary bile acid chenodeoxycholic acid?
A. Cholic acid
B. Deoxycholic acid
C. Ursodeoxycholic acid
D. Lithocholic acid
E. Taurocholic acid
Question 161:
Which cytochrome P450 enzyme is primarily responsible for the initial step in the synthesis of bile acids from cholesterol?
A. CYP1A1
B. CYP2D6
C. CYP7A1
D. CYP3A4
E. CYP2C19
Question 162:
Which of the following processes is essential for the recycling of bile acids from the intestine back to the liver?
A. Glucuronidation
B. Sulfation
C. Enterohepatic circulation
D. Deconjugation
E. Transamination
Question 163:
Which of the following molecules is NOT directly involved in the conjugation of bile acids in the liver?
A. Glycine
B. Taurine
C. Glucuronic acid
D. Sulphate
E. Acetyl-CoA
Question 164:
Which of the following statements about bile acids is TRUE?
A. They are primarily synthesised in the intestine.
B. They function to hydrolyse proteins.
C. They are reabsorbed in the jejunum.
D. They are derived from cholesterol.
E. They neutralise gastric acid.
Question 165:
Which of the following is NOT a function of cytochrome P450 enzymes in bile acid metabolism?
A. Hydroxylation of cholesterol
B. Conversion of primary bile acids to secondary bile acids
C. Detoxification of xenobiotics
D. Hydroxylation of bile acids
E. Regulation of bile acid synthesis via feedback mechanisms
Question 166:
What is the rate-limiting step in the synthesis of bile acids?
A. Conversion of cholesterol to pregnenolone
B. Conversion of cholesterol to 7-alpha-hydroxycholesterol
C. Conjugation of bile acids with glycine or taurine
D. Conversion of 7-alpha-hydroxycholesterol to cholic acid
E. Reabsorption of bile acids in the ileum
Question 167:
Which phase of the Migrating Motor Complex (MMC) is characterised by intense, rhythmic contractions?
A. Phase I
B. Phase II
C. Phase III
D. Phase IV
E. Phase V
Question 168:
Which cells act as the pacemakers for the gastrointestinal tract, generating slow waves of electrical activity?
A. Parietal cells
B. Chief cells
C. Interstitial cells of Cajal
D. Enteroendocrine cells
E. Goblet cells
Question 169:
What is the critical pH in saliva below which enamel demineralisation begins to occur?
A. 3.5
B. 4.5
C. 5.5
D. 6.5
E. 7.5
Question 170:
Which receptor does acetylcholine (ACh) primarily act on to stimulate gastric acid secretion?
A. Nicotinic receptor
B. Muscarinic M2 receptor
C. Muscarinic M3 receptor
D. Beta-adrenergic receptor
E. Alpha-adrenergic receptor
Question 171:
Which hormone stimulates the release of bicarbonate from the ductal cells of the pancreas to neutralise stomach acid in the duodenum?
A. Gastrin
B. Secretin
C. Cholecystokinin (CCK)
D. Histamine
E. Motilin
Question 172:
Which layer of the GI tract contains the myenteric plexus (Auerbach’s plexus)?
A. Mucosa
B. Submucosa
C. Muscularis externa
D. Serosa
E. Adventitia
Question 173:
Which enzyme is responsible for the final step of gastric acid production in parietal cells?
A. Carbonic anhydrase
B. HCO3-/Cl- exchanger
C. H+/K+ ATPase
D. Pepsinogen
E. Gastric lipase
Question 174:
Which medication class is used to block the H+/K+ ATPase and reduce gastric acid production?
A. H2 receptor antagonists
B. Proton pump inhibitors (PPIs)
C. Antacids
D. Anticholinergics
E. Beta-blockers
Question 175:
What is the primary cause of peptic ulcers related to Helicobacter pylori infection?
A. Increased histamine release
B. Increased acid production
C. Mucosal damage due to bacterial toxins and inflammation
D. Reduced bicarbonate secretion
E. Increased motility
Question 176:
Which receptor does histamine act on to stimulate gastric acid secretion?
A. H1 receptor
B. H2 receptor
C. H3 receptor
D. H4 receptor
E. M3 receptor
Question 177:
Which protein is essential for the absorption of dipeptides and tripeptides in the intestinal lumen?
A. Ferroportin
B. Ferroreductase.
C. DMT1 (Divalent Metal Transporter 1)
D. PEPT1 (Peptide Transporter 1)
E. Hephaestin
Question 178:
Which form of iron is more efficiently absorbed in the intestine?
A. Ferric iron (Fe³⁺)
B. Ferrous iron (Fe²⁺)
C. Ferric iron (Fe²⁺)
D. Ferrous iron (Fe³⁺)
E. Both forms are absorbed equally
Question 179:
Which transporter is responsible for exporting iron from enterocytes into the bloodstream?
A. PEPT1
B. Ferroportin
C. DMT1
D. DCTYB
E. Ferrireductase
Question 180:
Which protein is responsible for oxidising ferrous iron (Fe²⁺) to ferric iron (Fe³⁺) in the intestinal mucosa?
A. PEPT1
B. Ferroportin
C. DMT1
D. Ferrireductase
E. Hephaestin:
Question 181:
Which aquaporin is located on the luminal side of intestinal epithelial cells and facilitates water absorption?
A. Aquaporin 1
B. Aquaporin 2
C. Aquaporin 3
D. Aquaporin 10
E. Aquaporin 4
Question 182:
Which tongue papillae are primarily responsible for mechanical manipulation of food rather than taste perception?
A. Fungiform papillae
B. Foliate papillae
C. Circumvallate papillae
D. Filiform papillae
E. Taste buds
Question 183:
Which of the following organs is classified as retroperitoneal?
A. Stomach
B. Liver
C. Small intestine
D. Kidney
E. Spleen
Question 184:
Which protein inhibitor is linked to pancreatitis due to its effect on pancreatic protease activation, and how does hypercalcemia affect this condition?
A. SPINK1 (Serine Peptidase Inhibitor, Kazal Type 1)
B. Trypsinogen
C. Amylase
D. Lipase
E. Insulin
Question 185:
Which short-chain fatty acids are produced by fermentation of dietary fibres in the colon and what are their primary functions?
A. Butyrate and Propionate
B. Acetone and Acetoacetate
C. Palmitate and Stearate
D. Linoleic acid and Arachidonic acid
E. Cholesterol and Triglycerides
Question 186:
A 60-year-old woman with a history of chronic gastritis is assessed for her gastrointestinal motility. Which of the following cells are primarily responsible for initiating the rhythmic contraction of the stomach’s smooth muscle?
a) Interstitial cells of Cajal
b) Enteric glial cells
c) Enteroendocrine cells
d) Chief cells
e) Parietal cells
Question 187:
A patient with suspected primary biliary cirrhosis is being evaluated for bile acid abnormalities. Which of the following statements accurately describes the difference between primary and secondary bile acids?
a) Primary bile acids are synthesised from cholesterol in the liver, while secondary bile acids are formed by bacterial conversion in the intestines.
b) Secondary bile acids are synthesised from cholesterol in the liver, while primary bile acids are formed by bacterial conversion in the intestines.
c) Both primary and secondary bile acids are synthesised in the liver but serve different roles in lipid digestion.
d) Primary bile acids are formed in the stomach, while secondary bile acids are synthesised in the pancreas.
e) Secondary bile acids are primarily excreted through the kidneys, while primary bile acids are excreted through the liver.
Question 188:
A 70-year-old male is evaluated for symptoms of constipation. Which of the following is most likely to be affected in patients with decreased function of the migrating motor complex (MMC)?
a) Gastric emptying
b) Nutrient absorption
c) Faecal incontinence
d) Pancreatic enzyme secretion
e) Hepatic bile production
Med Wiz 