Ch.35 Jejunum and Ileum Flashcards
Length of small intestine
10 - 30 meters average 25m
Length of jejunum
17 - 28 meters
Where is the jejunum located
Left dorsal abdomen between loops of SC
Arterial supply of jejunum
Cranial mesenteric artery
Major jejunal artery ->arcuate vessel forms a loop with next major jejunal vessel
Vasa recta -> from arcuate vessel to intestinal wall
Venous drainage
Portal v
Length of ileum
0.7 meters
Arterial supply to ileum
Ileal artery a branch from the iliocecocolic artery -off of cranial mesenteric
Travels along ileum -> anastomoses with last jejunal artery
Describe the 3 layers of muscle of the ileocecal papilla
- Inner circular
- Central longitudinal layer from ileum
- Outer from circular m of cecum
arranged into semi circular lips
When does the true ileocecal sphincter contract
In sync with contractions of the cecal base
Where does digestion and absorption of nutrients take place
Upper half of the small intestine
What surrounds each villus
6-9 crypts of Lieberkuhn
Describe the mucosal folds and place circulates in the small intestine
Ha doesn’t have any
What makes up 90% of the small intestine epithelial cells
Columnar absorptive cells or enterocytes
What makes up the remaining 10% of small intestine epithelial cells
Mucous (goblet) cells
Enteroendocrine cells
Paneth cells
Undifferentiated columnar cells
Describe the activity of the columnar cells of the villi
After 2 divisions in the crypt they move to the villus as adult absorptive cells
Eventually extruded at the villi tip
Turnover time of 2-3 days
