gastroenterology

• What are the key components of the gastrointestinal system?

  GI tract, liver, pancreas, gall bladder
• What are the key roles of the GI system?

  Digestion, absorption, waste packaging
• How does the GI system produce waste and eliminate it?

  Through the process of defecation
• What can cause diarrhoea and constipation?

  Imbalance in water absorption and secretion
• What is the GI system composed of?

  Hollow organs from mouth to anus
• What happens during digestion in the GI system?

  Food is broken down and nutrients absorbed
• Where does digestion begin?

  In the mouth
• What aids in the breakdown of food in the mouth?

  Teeth, acid, and enzymes
• How does the body prepare for food before it enters the mouth?

  Salivary glands become active upon seeing or smelling food
• What is the role of mastication in digestion?

  Increases surface area for enzyme breakdown
• How much saliva is produced daily?

  2-4 litres per day
• What is the function of the oesophagus?

  Transports chewed food to the stomach
• What prevents food from passing through the oesophagus prematurely?

  Upper oesophageal sphincter
• How does material move through the GI system?

  By peristalsis, involuntary muscle contractions
• What is the pH level of the stomach?

  1.5-2
• What does the pyloric sphincter do?

  Controls release of chyme to the duodenum
• What are the two roles of the pancreas?

  Control blood sugar and secrete digestive juices
• What stimulates the secretion of digestive enzymes in the pancreas?

  Cholecystokinin (CCK)
• Why is bicarbonate-rich fluid secreted by the pancreas?

  To neutralize the acidity of chyme
• What is the endocrine role of the pancreas?

  Control blood sugar levels
• What do alpha cells in the pancreas secrete?

  Glucagon
• What do beta cells in the pancreas secrete?

  Insulin
• What is the liver's role in food conversion?

  Stores glucose as glycogen
• What does the liver detoxify?

  Alcohol and drugs from blood
• What is the function of the intestines?

  Enzymatic digestion and nutrient absorption
• What are enterocytes?

  Typical epithelial cells in the small intestine
• What do colonocytes do?

  Absorb fluid and electrolytes from faeces
• What is the role of stem cells in the intestinal epithelium?

  Crucial for turnover of intestinal epithelium
• What waste products might be found in stool?

  Dead cells, bacteria, water
• What determines the solidity of stool?

  The amount of water present in stool
• What induces the urge to defecate?

  Movement of faeces from colon to rectum
• What causes diarrhoea?

  Increased water secretion from intestines
• What is constipation?

  When stool moves too slowly through the colon
• What happens to carbohydrates we cannot digest?

  They are converted into fatty acids through fermentation
• How long does the entire digestive process take?

  24-36 hours
• What characterizes inflammatory bowel disease (IBD)?

  Abdominal pain, cramps, rectal bleeding, diarrhoea
• What is Crohn’s disease?

  Affects the entire digestive system
• What is a common treatment for Crohn’s disease?

  There are no definitive treatments
• What is the most widely held hypothesis on the pathogenesis of IBD?

  Overly aggressive immune responses in genetically susceptible hosts
• How often does the average person poop?

  3 times a day to 3 times a week