Fiber

Question 1

soluble fibers

Answer 1

fructans, psyllium, beta-glucans, pectins, gums, some hemicelluloses

Question 2

viscous fibers

Answer 2

psyllium, b-glucans, pectins, gums

Question 3

insoluble fibers

Answer 3

lignan, cellulose, some hemicellulose

Question 4

cellulose found where

Answer 4

major component of plant cell walls. It is abundant in bran, beans, nuts, root vegetables and apples.

Question 5

cellulose polymer of

Answer 5

glucose with b-1,4 bonds

Question 6

lignans found where

Answer 6

They are found in the stems and seeds of fruits.

Question 7

lignans made of

Answer 7

branched polymers of phenolic subunits

Question 8

hemicellulose found where

Answer 8

in bran, whole grains, and nuts.

Question 9

hemicelluloses made of

Answer 9

backbone: xylose, mannose, galactose
side chains: arabinose, glucuronic acid, galactose

acidic –> soluble

Question 10

pectins found where

Answer 10

apples, strawberries

Question 11

pectins made of

Answer 11

backbone: galacturonic acid

side chains: rhamnose, arabinose, xylose, fucose, and galactose

Question 12

gums made where

Answer 12

plants secrete to seal wounds

Question 13

gums made of

Answer 13

backbone w/ branches terminated in galacturonic acid

Question 14

beta-glucans found where

Answer 14

oats, barley, mushrooms

Question 15

beta-glucans made of

Answer 15

b-glucans are homopolymers of glucopyranose subunits.

Question 16

fructans found wehre

Answer 16

asparagus, leeks, onions, garlic, tomato and banana

Question 17

fructans made of

Answer 17

Fructan structure is fructose + glucose in 1,2 glycosidic bond, with a polyfructose chain bonded to the fructose in 1,6 bond.

Question 18

which fiber really good for bacteria

Answer 18

gums, pectans, betaglucans

fructans = prebiotic

Question 19

inulin is a

Answer 19

synthetic fructan

Question 20

psyllium =

Answer 20

metamucil

Question 21

soluble fibers do what

Answer 21

Soluble fiber delays gastric emptying, increases transit time through the GI, and decreases nutrient uptake.

Question 22

viscous fibers do what

Answer 22

Viscous fibers delay gastric emptying, decrease mixing of food with digestive enzymes, decrease nutrient diffusion, and increases small intestine transit time.

Question 23

insoluble fibers do what

Answer 23

Insoluble fiber decreases intestinal transit time and increases fecal bulk.

Question 24

SCFAs affect immune cells by

Answer 24

acting as a ligand for GPR43, and by inhibiting histone deacetylases (HDAC).

Question 25

SCFAs are nutrient source for

Answer 25

Short chain fatty acids produced by bacterial fermentation of fiber serve as a nutrient source for colonocytes, and promote immune tolerance of beneficial microorganisms.

Question 26

GPR43 on adipocytes

Answer 26

GPR43 is also expressed on adipocytes. Activation by short chain fatty acids inhibits insulin dependent storage of fatty acids, increasing their use by other tissues.