SI Digestion & Absorption Part 1 (Exam 1) Flashcards
The small intestine extends from the pyloric sphincter to the….
ileocecal sphincter/valve
Where do most of the major events of digestion and absorption occur?
SI
What are the 3 parts of the SI?
1) duodenum
2) jejunum
3) ilium
T/F: peristalsis in the SI is weaker than the stomach
true!
How long does chyme remain in SI?
3-5 hours
What is segmentation of the SI?
local mixing and churning of chyme with intestinal juices (sloshing it back and forth)
What is the purpose for SI to have large surface area?
test q
for majority of absorption in GI tract, it needs the room!
What is the longest part of the SI?
ileum
What is the shortest part of the SI?
jejunum
Plicae circulares are extensions of the __________ layer of the SI
submucosal
Vili are fingerlike extensions which greatly increases SA for absorption in the SI. The villi contain vascular capillaries and lacteal. What is a lacteal?
lymphatic capillary for fat absorption and transport
Microvilli are ________________ specializations of the lumen in the SI, and are also termed _____________
test q
enterocyte apical, brush border
Where are the enzymes located for final digestion of carbs, proteins, and lipids?
test q
brush border
Where are carriers and transporters located for absorption in the lumen of the SI?
test q
brush border
What 3 things increase SA in the SI?
test q
plicae circulares, villi, and specialized microvilli
