Intestinal and Colonic Absorption Flashcards Preview

Physiology (Gastrointestinal) > Intestinal and Colonic Absorption > Flashcards

Flashcards in Intestinal and Colonic Absorption Deck (18):
1

What is absorbed in the intestine?

solutes/water
monosaccharides
amino acids
lipids
vitamins
iron
calcium

2

What is absorbed in the colon?

solutes/water
ammonia
SCFAs

3

What is absorbed in the gallbladder?

solutes/water

4

Name 4 characteristics of the jejunum

long absorptive villi
microvillar brush border
no Brunner's glands
no Peyer's patches

5

Name 4 characteristics of the colon

columnar epithelium
goblet cells
long crypts
Paneth cells

6

Name 4 characteristics of the gallbladder

mucosal folds
columnar epithelium
no muscularis mucosa
no submucosa

7

What are the functions of the Na+ co-transporter?

transport glucose, galactose, amino acids, protons, vitamins

8

How are glucose/galactose transported into and out of the cell?

transported in by SGLT1
transported out by GLUT1

9

How are amino acids/peptides transported into and out of the cell?

transported in as dipeptides and tripeptides with H+
transported out as amino acids by specific transporters

10

Explain lipid transport

products of lipid digestion solubilized in lumen in micelles

products of digestion released into cells, reesterified to original lipids

lipids packaged in chylomicrons

chylomicrons go to lymphatic capillaries by exocytosis

11

Name the fat soluble vitamins and how they are absorbed in the intestine

Vitamins A, D, E, K

micelles form with bile salts

12

Name the water soluble vitamins and how they are absorbed in the intestine

B complex, vitamin C, folate, nicotinate, pantothenate

Na+-coupled transporter

13

How is Vitamin B12 absorbed in the intestine?

intrinsic factor-mediated

14

Explain urea absorption in the colon

urea from urea cycle absorbed in colon
ureases and proteases break urea down to ammonia or ammonium
ammonia released back into portal circulation
ammonium released in waste

15

Name some characteristics of the small intestines

villi
prominent brush border microvilli
sparse goblet cells
more than 20 endocrine cell types
rapid crypt to epithelial migration
absorption of amino acids, glucose, lipids, vitamins, and sodium

16

Name some characteristics of the large intestines

sparse brush border microvilli
abundant goblet cells
3 endocrine cell types
slow crypt to epithelial migration
prominent SCFA production and absorption

17

Name 2 types of medical therapy for malabsorptive disorders

re-hydration
anti-diarrheal agents

18

Name the 4 types of anti-diarrheal drugs

prostaglandin synthetase inhibitors
opioid agonists
serotonergic antagonists
adrenergic agonists