Digestive System Flashcards
Give examples of intraperitoneal organs
Stomach, some of small intestine
Give examples of retroperitoneal organs
Pancreas, part of duodenum
What is an omentum?
Double layer of visceral peritoneum - attaches organ to organ
What is the mesentry?
Double layer of visceral peritoneum that attaches organ to body wall
What are the 4 layers of the GI tract?
Mucosa
Submucosa
Muscularis externa
Serosa/adventia
What type of tissue is mucosa?
Epithelium, connective tissue and smooth muscle
What type of tissue is submucosa?
Dense irregular connective tissue
WHat is the serosa?
Serous membrane that covers the structures within peritoneal cavity
What blood vessels supply the GI tract?
Celiac trunk, superior mesentreric artery and inferior mesentric artery
How is blood drained?
Via the hepatic portal system
Name 3 hormones that control digestive function
Gastrin, secretin, cholecystokinin (CCK)
What are carbohydrates broken down into?
Simple sugars
What are proteins broken down into?
amino acids
What are lipids broken down into?
Fatty acids & monoglycerides
What is broken down in the mouth?
Carbohydrates and lipids
What is digested in the stomach?
Proteins
What is digested in the small intestine?
Carbs, proteins & lipids
What enzymes are released in the mouth?
Salivary amylase, lingual lipase
What cells produce HCL & intrinsic factor?
Parietal cells
What cells produce pepsinogen?
Chief Cells
What do enteroendocrine cells produce?
Gastrin
Name 3 phases of gastric activity - in order
Cephalic phase
Gastric Phase
Intestinal phase
Where does the pancreas open into?
Duodenum, sphincter of Oddi
Where are Acini cells located and what do they produce?
Pancreas, secrete propeptidases, amylase, lipase, ribonuclease
What do Duct cells secrete?
Water and sodium bicarbonate
What do alpha cells secrete?
Glucagon
What do beta cells secrete?
Insulin
What role does the liver play in digestion?
Bile production
Where is bile stored?
In the gall bladder
Name 3 parts of the small intestine
Duodenum
Jejunum
Ileum
What does cholecystokinin do?
Causes release of enzymes from acini cells, release of bile, relaxation of sphincter of Oddi. Reduces gastric motility & secretion in stomach.
What does secretin do?
Causes release H2O & sodium bicarbonate from duct cells. Liver secretes bile. Reduces gastric motility.
What does trypsin activate to digest protein?
Propeptidases eg trypsinogen, carboxypeptidase
How are lipids absorbed?
As micelles by diffusion and as cholymicrons in interstitial fluid
Where is water absorbed?
Large intestine
