9 21 Nutrient digestion and absorption 1-Table 1

Question 1

what are the common maronutrients found in a “western” dite.

Answer 1

Carbohydrates (polysaccharides, Disaccharides, monosaccharides); Proteins; Fats (Triacylglycerol, phospholipids; cholesterol).

Question 2

Carbs that can not be digested by human enzymes – exemplified by a beta sugar configuration.

Answer 2

Dietary Fiber

Question 3

describe how carbs are digested/absorbed

Answer 3

Mouth(Amylase); Duodenum (Pancreatic amylase); Small intestine (Maltase, Sucrase, Lactase). Break the carbohydrates down to monosacharides.

Question 4

explain lactose intolerance

Answer 4

70% of population Hypolactasia; don’t absorb lactase, lactase will get absorbed and digested by the gut bacteria.

Question 5

explain fructose malabsorption.

Answer 5

GLUT 5 mutation could lead to inability to inability to absorb Fructose.

Question 6

average amount of this macromolecule in western diet is 300 g/day

Answer 6

Carbohyderates

Question 7

what are the constituents of a carbohyderate?

Answer 7

polysaccharides (starch, glycogen); disaccharides (sucrose, lactose, maltose); monosaccharides (fructose, glucose, galactose);; non-digestible carbs (fiber)

Question 8

polysaccharides

Answer 8

starch (65%)/ glycogen (.0%)

Question 9

what is starch

Answer 9

glucose linked together, mostly linear, some branches. (flour, corn, potatoes)

Question 10

Disaccharides

Answer 10

sucrose(25%) lactose (6%); maltose

Question 11

what is sucrose

Answer 11

Glucose -alpha(1,2)-Fructose

Question 12

what is lactose

Answer 12

Galactose-beta(1,4)-glucose

Question 13

what fructose

Answer 13

fruit sugar,, and the monomer of sucrose.

Question 14

Monosaccharides

Answer 14

fructose,glucose (3%) and galactose

Question 15

non-digestible carbs

Answer 15

fiber!

Question 16

Amount of proteins in day avg.

Answer 16

100g/day

Question 17

where do we get glycogen?

Answer 17

meat!

Question 18

amount of fats in day?

Answer 18

80g/day triclyglycerol;phospholipids’cholesterol

Question 19

what are the three components of fats?

Answer 19

triachyglycerol; phospholipids’; cholesterol

Question 20

what is starch?

Answer 20

mostly unbranched amylose linked alpha 1,4: plus some occasionally branched amylopectin linked alpha 1,6;

Question 21

what is sucrose?

Answer 21

glucose with alpha 1,2 link to fructose

Question 22

what is lactose?

Answer 22

galactose beta 1,4 link to glucose

Question 23

so what links do we break to break starch?

Answer 23

alpha 1,4, and some alpha 1,6

Question 24

what is digestion in general

Answer 24

the way that we break polymers to monomers

Question 25

carbohyderate digestion and absorption summary!

Answer 25

h (picture on slide 9)

Question 26

what is the first digestive enzyme?

Answer 26

salivary amylase

Question 27

describe the basic path of digestion

Answer 27

salivary amylase; pancreatic amylase; maltase;surase,lactase.

Question 28

pancreatic amylase

Answer 28

breaks long chains of the startch to disacerides

Question 29

what does maltase do?

Answer 29

breaks matose to glucose molecules (2 of them)

Question 30

they break the disacherides to monosacherides

Answer 30

what is a disacherideases

Question 31

what does sucrase do?

Answer 31

they breack sucrose to glucose and fructose

Question 32

what does lactase do?

Answer 32

break lactose to glucose and galactose.

Question 33

what are the monomers that can be absorbed?

Answer 33

glucose, fructose, galactose, and D-Xylose

Question 34

why is the small intestine not at pH 2 like the stomach

Answer 34

secrete bicarbonate in the small intestine to buffer back to around 7 pH

Question 35

moves glucose and gallactose into the epitheilial

Answer 35

SGLT1 (Na cotransporter)

Question 36

moves glucose and galactose into the epithelial cell when eat alot of sugars

Answer 36

GLUT2

Question 37

move the fructose down its concentration gradient into the epithelial cells

Answer 37

GLUT 5

Question 38

move glucoes fructoes and galactose from the epithelial to the interstitial space

Answer 38

GLUT2

Question 39

that is in table sugar?

Answer 39

Sucrose or (glucose -alpha 1,2 bound to frutose)

Question 40

corn syrup

Answer 40

mostly glucose, some maltose and isomaltose (hydrolyzed corn starch

Question 41

high fructose corn syrup

Answer 41

corn syrup processed to convert 50% of glucose to fructose

Question 42

Honey

Answer 42

82% carbohydrate. (38% fructose 31% glucose, 13% di and oligosaccharides)

Question 43

agave syrup

Answer 43

55%-90% fructose, remainder of carbohydrate is mostly glucose.

Question 44

under what condition might cane sugar and highfructose corn syrup affect the body differently?

Answer 44

you need a disaccharidase to hydrolize this (sucrase). (it is about the same as table sugar). If sucrase is the rate limiting step, then there will be a difference between high fructose corn syrup and sugar (there doesn't seem to be much evidence for this. Therefore it really doesn't matter that much.

Question 45

why change glucose to fructose

Answer 45

fructose tastes sweeter than glucose

Question 46

how do we effectively get all digested macronutrients absorbed?

Answer 46

about 9000 m2 surfacd area in the villi and microvilli

Question 47

what transporter is likely to cause fructose malabsorption?

Answer 47

GLUT 5

Question 48

what could lead to bloating, intestinal cramps and gas after the consumption of pizza and ice-cream

Answer 48

lactose intolerance! not enough lactase! don't break down lactose (milk sugar), but the gut bacteria aborb it and emit a lot of gas!

Question 49

what does lactase do?

Answer 49

break lactose into the monomers galactose and glucose

Question 50

what is hypolactasia

Answer 50

it is a lack of lactase in the brush border microvilli

Question 51

what percent of people are hypolactaseic?

Answer 51

70% of people.

Question 52

what happens to the blood glucose of a hypolactasia person when consume milk?

Answer 52

it goes up a tiny part

Question 53

what happens to the blood glucose of a non-hypolactasia person when consume milk?

Answer 53

it spikes why up!

Question 54

how is the blood glucose different after absorbing milk? (for hypolactasia/ normal)

Answer 54

normal would spike and hypolactasia would not!

Question 55

after lactose consumption: why blood sugar spike for "normal" and why H2 spike fore "hypolactasia"

Answer 55

the blood sugar goes up as lactate broken down and H2 is from bacterial metabolism

Question 56

compare the mean breath H2 for hypolactasia vs. non-hypolactasia ("normal")

Answer 56

the breath pH would spike for hypolactasia and pretty flat for "normal"

Question 57

what is the difference in a alpha vs. a beta sugar conformations

Answer 57

the OH of the #1 carbon is oriented "down" on an alpha glucose, and "up" on a beta glucose. (in reference to the carboxy group on the #6 carbon.

Question 58

why do you get diarrhea with a lactose intolerance?

Answer 58

extra lactase not absorbed and raises the osmolarity of the intestines

Question 59

why do we care if the sugar is oriented alpha or beta?

Answer 59

digestive enzymes are specific for either the alpha or the beta configuration.

Question 60

what is digestible vs. non digestible fiber?

Answer 60

insoluble fiber has only the beta 1,4! and soluble fiber has some beta 1,3 (looks like an alpha bond)

Question 61

what is dextrose/

Answer 61

Glucose! (D-Glucose)

Question 62

Soluble fiber?

Answer 62

gummy, viscous. digeste/partially metabolized by intestinal bacteria. binds cholesterol and inhibits its absorption

Question 63

insoluble fiber

Answer 63

richer in wheat bran. prevent constipation, possibly diverticular disease.

Question 64

what type of enzymatic activity is most likely responsible for beano's effectiveness?

Answer 64

probably an alpha galactosidase to break the alpha bond between the galactose and glucose and galactose and galactose molecules found in the carbs in beans.

Question 65

what happens when you can't fully digest carbs?

Answer 65

excessive colonic bacterial fermentation: gas, bloating, discomfort, and diarrhea (osmotic diarrhea).