Flashcards in Intestinal and Colonic Absorption Deck (18):
What is absorbed in the intestine?
What is absorbed in the colon?
What is absorbed in the gallbladder?
Name 4 characteristics of the jejunum
long absorptive villi
microvillar brush border
no Brunner's glands
no Peyer's patches
Name 4 characteristics of the colon
Name 4 characteristics of the gallbladder
no muscularis mucosa
What are the functions of the Na+ co-transporter?
transport glucose, galactose, amino acids, protons, vitamins
How are glucose/galactose transported into and out of the cell?
transported in by SGLT1
transported out by GLUT1
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
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
Name the fat soluble vitamins and how they are absorbed in the intestine
Vitamins A, D, E, K
micelles form with bile salts
Name the water soluble vitamins and how they are absorbed in the intestine
B complex, vitamin C, folate, nicotinate, pantothenate
How is Vitamin B12 absorbed in the intestine?
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
Name some characteristics of the small intestines
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
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
Name 2 types of medical therapy for malabsorptive disorders