GI 15 Flashcards
What are the two types of micronutrients?
- Vitamins
* Trace elements
What are the fat soluble vitamins?
A, E, D
What is the main goal of carbohydrate digestion?
To break those long chains down into oligo/disaccharides
What is one of the most important enzymes for carbohydrate digestion?
Amylase
Where does Amylase in carbohydrate digest originate?
In the pancreas
What kind of enzyme is Amylase?
An alpha (1,4) endoglycosidase
How is the meaning of amylase being an endoglycosidase?
It cleaves glycosidic bonds between subunits of polysaccharides
What happens once amylase breaks down the polysaccharide into a disaccharide?
To break it down into monosaccharides
What is the breakdown of disaccharides into monosaccharides facilitated by?
The brush border enzymes of the SI
What are brush border enzymes?
Enzymes in the SI intestine that are specific for breaking down different disaccharides
What are three brush border enzymes?
- Maltase
- Sucrase
- Lactase
What does Maltase do?
Breaks down Maltose into two glucoses
What does Sucrase do?
Breaks down sucrose into glucose and fructose
What does Lactase do?
Breaks down lactose into glucose and galactose
What happens when somebody lacts Lactase?
They have lactose intolerance and further down the line the unbroken down lactose can affect water balance
What happens once disaccharides are cleaved into monosaccharides?
They can be absorbed across the intestinal epithelium
What kind of transport is used for the absorption of Glucose/galactose?
Secondary active transport
Which transporter brings glucose into the intestinal epithelial cell?
SGLT, the sodium glucose transport
How does SGLT-1 (sodium glucose cotransporter) work?
It brings glucose into the intestinal epithelial cell by bringing one molecule of glucose/galactose along with two Na+ down its conc. gradient
How does Glucose/Galactose exit the intestinal epithelial cell?
It diffuses through facilitated diffusion through the GLUT2
What does GLUT2 do?
Allows glucose/galactose and fructose to exit the intestinal epithelial cell through facilitated diffusion
What maintains the conc gradient when SGLT-1 is working?
The sodium potassium ATPase
How does Fructose enter the intestinal epithelial cell?
By facilitated diffusion through GLUT5
What does GLUT5 do?
Allows fructose to enter the intestinal epithelial cell through facilitated diffusion
