Topic 9 Gastrointestinal system_4 Sm intestine Pancreas Flashcards
Large surface area for digestion and absorption (Key)
Small intestine
Small intestine 3 regions
1) duodenum - first part of sm intestine
2) jejunum - folding
3) ileum - 3rd portion of the sm intestine b/w the jejunum and cecum
Small intestine…
ridges in the mucosa/ submucosa that increase surface area
Circular folds
T/F - Most digestion and absorption occur in the small intestine
True
Small intestine…
the mucosal layer has____to increase surface area
Villi - Finger-like projections that increase surface area
Small intestine …
Each villus is covered in______?
epithelium
Small intestine…
Cells of the epithelium
Absorptive cells (digestion/absorption) Goblet cells (mucous - for protection and coating) Paneth cells (kill bacteria) Enteroendocrine cells (secrete hormones)
Small intestine…
Absorptive cells have?
microvilli (brush border - BB enzymes)
Small intestine... each villus (3)
an arteriole, a venule and a lacteal
Small intestine…
In order to absorb nutrients, chyme needs to be mixed with these (2)
Intestinal and pancreatic juices
Small intestine…
what are the 3 pathways for absorbed nutrients?
1) blood stream (carbohydrates, proteins, water, electrolytes, water-soluble vitamins) and go to the liver
2) the lymphatics (lipids - fats) via a lacteal (only in sm intestine)
3) remaining food passes through the ileocecal valve/ sphincter into the large intestine
Transition into the cecum of the large intestine from the sm intestine
ileoceal valve/ sphincter
Sits posterior to the stomach
has both endocrine and exocrine functions
Pancreas
Secretes pancreatic juice (water, salts, sodium bicarbonate, enzymes into the duodenal lumer
the exocrine function of the pancreas
- sodium bicarbonate - neutralizes acids of stomach
Pancreatic juices are secreted into the proximal duodenum via (2)?
2 main ducts
1) common duct formed by 2 ducts: pancreatic and common bile duct from liver/gallbladder
2) accessory duct - which dumps directly into the deodenum
