GIT Digestion & Absorption Flashcards
Enzymes produced by which organ are needed for digestions of macromolecules
Pancreas
Which enzymes in the small intestines are needed to break down carbs
Sucrase, lactaste
Which enzyme in the small intestines is needed to break down proteins
Peptidase
Which enzyme in the stomach is needed to break down proteins
Pepsin
Triglycerides are proken down to what
2’-Monoglycerides
Fatty acids
Proteins are broken down to what
Amino acids (40%) Di-, Tripeptides (60%)
Carbohydrates are broken down to what
Glucose, Galactose,
Fructose
Which transporter carries glucose and galactose into epithelial cells
Sodium-Glucose Linked Transporter (SGLT 1)
By which type of diffusion do galactose, fructose and glucose get absorbed into the blood stream
Facilitated diffusion with a GLUT 2 transporter
Which transporter carries peptides into epithelial cells
Na-H antiporter
By which type of diffusion do peptides get absorbed into the blood stream
simple diffusion and some protein-mediated transport
Substances found in the micelles
Fatty acids (long chain) 2-monoglyceride Cholesterol Lysolecithin Vitamins A, D, E, K Bile salts
Which structure allows for the diffusion of fat into epithelial cells
Micelles
In the epithelial cells, triglyceride is resynthesized and forms what structure
Chylomicrons
How do chylomicrons leave the intestine
Via the lymphatic circulation
Chylomicrons that leave the intestine via the lymphatic circulation enter the bloodstream via what duct
The thoracic duct
Which type of fatty acids can be absorbed by simple diffusion
directly into the bloodstream
water-soluble short-chain fatty acids
Which vitamins are fat soluble
Vitamins A, D, E, K
Which vitamins are water soluble
Vitamins B and C
Which water soluble vitamin is not dependent on Na+ transport
B12
What do chylomicron convert to
VLDL
Where does absorption of most divalent ions and water-soluble vitamins begin
Duodenum
What redissolves calcium and iron salts, which facilitates
their absorption in the small intestine
Stomach acid
Calcium absorption is enhanced by
Calbindin
What induces synthesis of calbindin
Calcitriol (active vitamin D)
What is the name for active vitamin D
Calcitriol
Which protein facilitates iron
absorption
Ferritin
What is absorbed in the jejunum
Water and electrolytes
What is absorbed in the ileum and what is secreted
Water, sodium, chloride, and potassium
While bicarbonate is secreted
What is absorbed in the distal ileum
Bile salts and intrinsic factor with Vitamin B12
What is absorbed in the colon
Water and sodium chloride,
Main function of the rest of the colon after the transverse colon
Storage
Effect of aldosterone on the colon
Increases sodium and
water reabsorption and potassium secretion
Two types of diarrhea
Osmotic and Secretory
What type of diarrhea does lactase in deficiency cause
Osmotic
What causes osmotic diarrhea
Presence of non-absorbable solutes in the intestines
What causes secretory diarrhea
Excessive secretion of fluid by crypt cells
What is administered to patients with diarrhea
Oral rehydration containing glucose, sodium, bicarbonate and chloride
