Section 7: Digestion and Absorption of Carbohydrates and Protein Flashcards Preview

Physiology > Section 7: Digestion and Absorption of Carbohydrates and Protein > Flashcards

Flashcards in Section 7: Digestion and Absorption of Carbohydrates and Protein Deck (61):
1

Which complex molecules can be absorbed directly across the epithelium

none, not through cell membranes or tight junctions

2

Enzyme locations for digestion and absotption of carbohydrates:

brush border and lumen

3

Final acts of digestion enzymes are here:

brush border

4

Which glucose bonds are harder to break?

1,6

5

Enzyme in carbohydrates breakdown:

alpha amylase of pancreas, alpha dextrinase and glucoamylase

6

Fructose + Glucose:

sucrose

7

2 transport proteins;

glucose carrier and fructose carrier

8

test of carrier mediated transport:

transported against concentration gradient, tube in rabbits stomach, infuse bolus of glucose solution, lumen of stomach now has high glucose concentration, glucose concentration higher in lumen than blood, no glucose after 90 minutes. Below dotted line = active transport

9

Glucose sugar levels:

90 mg percent (90 mMol)

10

What sugar will be absorbed preferentially over glucose?

galactose

11

Can provent functions of glucose carrier required for absorption:

oubain (poison), depeds on metabolic enegy, lumen Na+ depeneded

12

Glucose and galactose on this protien:

SGLT

13

What is SGTL:

cotransporter, one is not transported without the other

14

Glucose is moved out on the basolateral side via this:

GLUT 2

15

Ouabiain blocks:

the Na/K pump, Na increases in the cell, prevents glucose transport

16

True or False? Transport of glucose is concentration dependent.

F

17

fructose transport

can't go against a concentration gradient, can't be poisoned by oubain, no ATP involved, no sodium involved, ,

18

Which basolateral transporter moves fructose out of the cll?

GLUT 2, facilitated diffusion

19

True or False? lactose intolerabitliy leads to a decreases in luminal osmolarity.

F. increase

20

True or False? Fluid accumulates in the lumen of the stomach in people with lactose intolerance.

T

21

What are the more immediate issues that lead to diarrhea for lactose intolerant people?

luminal distension and enhanced peristalsis

22

Where do bacteria attack lactose in the gut?

small and large intestines

23

Liters of water entering the intestines each day:

8-10L (check)

24

True or False? High fructose corn syrup is worse for you than sugar.

F

25

Sugar is high in __ and low in ___:

calories, nutriiton

26

Dietary fibers:

cellulose, hemicelluose, or pectins

27

These enzymes don't absorb cellulose, hemicelluose, or pectins

pancreatic or brush border enzymes

28

Organic anions of dietary fiber are:

osmoticaly active, less likely to be constipated

29

Bacteria break fibers dow to:

short chain fatty acids, H2, CO2, and methane

30

Short chain fatty acids that fiber is broken down to:

acetate, propionate, butyrate

31

True or False? None of the short chain fatty acids that are produced by the break down of fibers are absorbed.

F. Some are

32

Toxins produced by bacteria can cause:

secretory diarrhea

33

Protiens in the lumen:

125gm/day or 20% of the diet in U.S.

34

Amount of protein enzymes in the lumen per day:

30 mg/ day

35

This makes up 25 mg/day of the protein in the lumen:

dead epithelial cells

36

Turnover rate of epithelial cells in the lumen:

5 days

37

5 carriers in the proximal intestines:

Neutral AA's, Basic AAs, Acidic AAs, Imido AA, Di- and tri-peptides

38

First real protease:

pepsin

39

What enzyme does most of the work of breaking proteins down?

pancreatic protease

40

Enzymes involved in protein digestion:

pancreatic protease and pepsin

41

Bile acids, and water soluble amino acids are returned via:

hepatic portal vein

42

What peptidases break down the smaller peptides?

intracellular

43

Characteristics of amino acids absorption:

transport aginst a concentration gradient, competition between amino acids, poisoned by ouabia (Na is involved), depends on metabolic energy to be absorbed, depend on luminal sodium

44

Amino acids absorption in the duodenum and jejunum:

Na coupled, proved by polarizing epithelial cells, Na/K pump always on the basolateral side

45

True or False? Amino acids acid absorption is always transported via this type of transport:

secondary active transport

46

Vitamin B12 is aka:

Cobalamin

47

Vitamin B12 is needed for:

making rbc

48

only thing the stomach does that is required for living

intrinsic factor secreted by parietal cells to absorb B12 in the blood

49

How is CBL broken down in the stomach

pepsin and the acidity of the stomach

50

Vitamin:

essential to live, you can't make yourself

51

What cells secrete intrinsic factor?

parietal cells

52

What is secreted by gastric glands which then binds to cobalmin

Haptocorrin,

53

What is required for the absorption of B12?

intrinsic factor

54

Pernicious anemia:

large, odd red blood cells that get stuck in the capillaries, feed raw liver, they get better

55

When is CBL released into the small intestines?

proteolyic degradation of haptocorin

56

Why did the liver make the patients better?

store of B12 in the liver

57

What are absorbed in the jejunum?

Trigycerides, fat soluble vitamins, cholesterol, and lecithin

58

When is most absorption done?

mid jejunum

59

Why are fats harder to digest?

not water soluble

60

Reabsorbed in the ileum:

bile salts and V12

61

What sugars make up the largest and smallest components of our diet?

sucrose (30%) and lactose (6%)