lecture 3 Flashcards
What are the main hormones of the gastrointestinal tract (GIT)?
Gastrin, secretin, cholecystokinin (CCK), motilin, and gastric inhibitory peptide (GIP)
What is the role of gastrin?
Gastrin stimulates the secretion of gastric acid (HCl) from parietal cells in the stomach.
What is the role of secretin in digestion?
Secretin stimulates the pancreas to release bicarbonate, which neutralizes acidic chyme in the duodenum.
What does cholecystokinin (CCK) do in the digestive process?
CCK stimulates the release of bile from the gallbladder and pancreatic enzymes for fat and protein digestion.
What cells in the pancreas secrete insulin?
Beta cells in the islets of Langerhans
What is the function of insulin?
Insulin lowers blood glucose by promoting glucose uptake by cells and glycogen storage.
What cells in the pancreas secrete glucagon?
Alpha cells in the islets of Langerhans
What is the role of glucagon in the body?
Glucagon raises blood glucose levels by promoting glycogen breakdown in the liver.
What are the main digestive enzymes secreted by the pancreas?
Amylase (carbohydrates), lipase (fats), and proteases like trypsin and chymotrypsin (proteins)
What is the function of pancreatic lipase?
Lipase breaks down fats into fatty acids and glycerol for absorption in the small intestine.
How do the pancreatic ducts and biliary ducts interact?
The pancreatic duct and the common bile duct join at the ampulla of Vater, releasing their contents into the duodenum via the sphincter of Oddi.
What is Type 1 diabetes mellitus?
An autoimmune condition where the body attacks insulin-producing beta cells in the pancreas, leading to insulin deficiency.
What is Type 2 diabetes mellitus?
A metabolic disorder characterized by insulin resistance, where the body’s cells do not respond properly to insulin, often associated with obesity.
What is gestational diabetes?
A form of diabetes that occurs during pregnancy, where the body cannot produce enough insulin to meet increased demands.
What are the three phases of digestion?
The cephalic phase, gastric phase, and intestinal phase
What happens during the cephalic phase of digestion?
The sight, smell, or thought of food stimulates the vagus nerve to prepare the stomach for digestion by increasing gastric secretions.
What happens during the gastric phase of digestion?
Food in the stomach triggers the release of gastric acid and enzymes for digestion, while the stomach stretches to accommodate food.
What happens during the intestinal phase of digestion?
The presence of chyme in the small intestine stimulates the release of digestive hormones and enzymes while slowing gastric emptying.
What is the embryonic origin of the gastrointestinal tract (GIT)?
The GIT develops from the endoderm layer of the embryo.
What are some common disorders of the gastrointestinal tract (GIT)?
Peptic ulcers, gastroesophageal reflux disease (GERD), Crohn’s disease, irritable bowel syndrome (IBS), and celiac disease
What causes gastroesophageal reflux disease (GERD)?
GERD is caused by the backflow of stomach acid into the esophagus, often due to a weak lower esophageal sphincter.
What is Crohn’s disease?
Crohn’s disease is a chronic inflammatory condition that can affect any part of the GIT, leading to pain, diarrhea, and malnutrition.
What is the role of ghrelin in hunger?
Ghrelin is a hormone produced by the stomach that stimulates appetite and signals hunger to the brain.
What is the role of leptin in satiety?
Leptin is a hormone produced by fat cells that signals the brain to reduce appetite and promotes the feeling of fullness.
How does acupuncture help with gastrointestinal diseases?
Acupuncture may help reduce symptoms of GI diseases by regulating the autonomic nervous system, reducing inflammation, relieving pain, and improving gut motility.
What points are commonly used in acupuncture for GI issues?
Common points include ST36 (Zusanli), CV12 (Zhongwan), and LI4 (Hegu).
