Digestion enzyme stuff first aid

Question 1

alpha amylase does what and is secreted from where

Answer 1

starch digestion

Question 2

Lipase and phospholipase do what

Answer 2

Fat digestion

Question 3

Proteases do what?

Answer 3

Proten digestion

Question 4

Trypsinogen

Answer 4

Converted to trypsin, then activates other coenzymes and creates more trypsin.

Question 5

Salivary amylase’s role in carbohydrate digestion

Answer 5

Starts the process by hydrolyzing alpha 1,4 linkages to yield disaccharides (maltose and alpha limit dextrin,maltotriose)

Question 6

Pancreatic amylase

Answer 6

hydrolyzes starch to oligosaccharides and disacchardies

Question 7

Oligosaccharide hydrolase

Answer 7

These are located at the brush border of the intestines, teh rate limiting step in carbohydrate digestion, they produce monosaccharides from the disaccharides and oligosaccharides.

Question 8

Carbohydrate absorption is interesting. Only monosaccharides like- Glucose, galactose, fructose- are absorbed by enterocytes. After that, GLucose and galactose are taken up by what?

Answer 8

SGLT-1

Question 9

Fructose is taken up by facilitated diffusion by

Answer 9

GLUT-5

Question 10

Glucose, Galactose, and Fructose are all transported into the blood by

Answer 10

GLUT-2

Question 11

What are the two types of digestive enzymes>

Answer 11

1) Luminal

2) Membrane Enzymes

Question 12

Basal cells in enterocytes are located where?

Answer 12

Crypts…Stem cells move up the villi and differentiate as they do. Stem cells migrate asymmetrically

Question 13

Gut cells slough off at what rate

Answer 13

Every 3-5 days. Newly differentiated stem cells take their place.

Question 14

Which portion of the gut is integral to the reabsorption of vitamin B12 and Bile Acid.

Answer 14

Ileum

Question 15

How much of the gut can be removed without any major impact

Answer 15

60-70 percent

Question 16

What are the barriers to absorption in the enterocyte?

Answer 16

1) Unstirred water layer, this is an especially formidable barrier to fats
2) Glycocalx- no idea what it does, doesnt matter
3) Microvilli Membrane (enterocyte membrane)
4) Cytoplasm
5) Basolateral Membrane
6) Basement Membrane
7) Capillary wall (fenestration)

Question 17

Fat cells leave the enterocytes in what?

Answer 17

Chylomicrons

Question 18

Glucose absorption requires what?

Answer 18

Oxygen

Question 19

Starch and Glycogen are first broken down by salivary amylase into?

Answer 19

1) alpha dextrins (1,4 and 1,6)
2) Maltotriose
3) Maltose

Question 20

Alpha dextrin 1,4 is digested mainly by what membrane enzyme?

Answer 20

Isomaltase

Question 21

Alpha 1,6 digested by

Answer 21

Glycoamylase (60)
Sucrase (20)
Isomaltase (20)

Question 22

Maltotriose digested by?

Answer 22

G, S I (25, 25, 50)

Question 23

Maltose digested by?

Answer 23

G, S, I (25, 25, 50)

Question 24

Glucose and Galactose taken into the enterocytes by

Answer 24

SGLT-1

Question 25

See carriers for carb absorption slide and recognize that SGLT-1 is responsible for transporting Na and Glucose or Galactose into the cell. Na then is pumped out via the Na/K ATPase transporter,,,so this SLGT-1 transport depends on Na/K working and I guess vice versa. The transporter itself dumps what its carrying and moves back to the apical membrane.

Answer 25

ok

Question 26

WHat the fuck is GLUT-5

Answer 26

carries fructose into the cell

Question 27

What the fuck is GLUT-2

Answer 27

Carries all of the simple sugar, Glu- Gal- Fru, across the basolateral membrane and out of the enterocyte.

Question 28

Knowing what we know about these transporters, what would happen to the amount of glucose being digested if you added a bunch of galactose into the system?

Answer 28

The amount of glucose in the system would go down because you have two things competing for the same transporter

Question 29

Most common enzyme deficiency?

Answer 29

Lactase deficiency

Question 30

What begins the digestion of protein?

Answer 30

Pepsin

Question 31

What kind of enzyme is pepsin

Answer 31

Endopeptidase (cleaves interior peptide linkages)

Question 32

In regards to protein absorption, remember that the absorption of peptides is separate from the absorption of free amino acids

Answer 32

ok

Question 33

What are the 3 major enzymes of fat digestion

Answer 33

1) Pancreatic Lipase 2) Cholesterolester Hydrolase 3) Phospholipase A2

Question 34

Pancreatic Lipase does what?

Answer 34

Breaks up triglycerides into 2 Monoglyceride and 2 free fatty acids

Question 35

Cholesterolester Hydrolase does what

Answer 35

Cleaves the fatty acids from the 3 position of cholesterol and fat soluble vitamins

Question 36

Phospholipase A2 does what?

Answer 36

Lecithin to lysolecithin