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Flashcards in G11 Deck (18):
1

What are the Pancreatic enzymes?

a-amylase
Lipase
Phospholipase A
Colipase
Proteases (trypsin, chymotrypsin, elastase, carboxypeptidases)
Trypsinogen

2

a-amylase function.

Starch digestion

*Secreted in active form

3

What pancreatic enzymes are involved in fat digestion?

Lipase
Phospholipase A
Colipase

4

What are pancreatic proteases secreted as?

Proenzymes (AKA zymogens)

5

How is trypsinogen converted to trypsin?

Enterokinase/Enteropeptidase

6

Where are Enterokinase/Enteropeptidase enzymes secreted from?

Duodenal mucosa

7

What are the enzymes involved in Carbohydrate digestion?

Salivary amylase
Pancreatic amylase
Oligosaccharide hydrolases

8

Salivary amylase.

Starts digestion
Hydrolyzes a-1,4 linkages to yield disaccharides (maltose and a-limit dextrins)

9

Pancreatic amylase.

Highest concentration in Duodenal lumen
Hydrolyzes starch to oligosaccharides and disaccharides

10

Oligosaccharid hydrolases.

Brush border of intestines
Rate-limiting step in carb digestion
Produce monosaccharides from oligo- and disaccharides

11

Only ______________ are absorbed by enterocytes.

Monosaccharides
-glucose
-galactose
-fructose

12

In the enterocytes, Glucose and Galactose are taken up by what?

SGLT1 (Na+ dependent)

13

In the enterocytes, how is Fructose taken up?

Facilitated diffusion by GLUT-5

14

How are monosaccharides transported to the blood?

GLUT-2

15

What is the function of the D-xylose absorption test?

Distinguishes GI mucosal damage from other causes of malabsorption

16

Where is Iron absorbed?

Duodenum (as Fe2+)

17

Where is Folate absorbed?

Jejunum

18

Where is Vit. B12 absorbed?

Terminal Ileum (along with bile acids)
*Requires Intrinsic Factor