1.2

Question 1

are homoglycans oligosaccharide, polysaccharide, or disaccharides?

Answer 1

they are considered polysaccharides because they are a polymer

Question 2

residues

Answer 2

repeating units

Question 3

sugars

Answer 3

are the only ones that can be branched

Question 4

monosaccharides

Answer 4

n=1

Question 5

disaccharides

Answer 5

n=2

Question 6

oligosaccharides

Answer 6

n=3 to n=10

Question 7

polysaccharide

Answer 7

n > 10

Question 8

what are the simplest from of polysaccharides?

Answer 8

disaccharides

Question 9

polysaccharides are composed of?

Answer 9

they have monosaccharides (at least two) that have a oxygen glycosidic linkage by a covalent bond

Question 10

describe lactose

Answer 10

• it is a type of disaccharide that has a glycosidic linkage between beta 1 of galactose and beta 4 of glucose.
• because it has a head to tail fashion, it is reducing
• overall: Beta-D-galactopyranosyl (1->4) B-D-glucopyranose

Question 11

how much of lactose is in milk?

Answer 11

10 (w/w) which means about 10%

think of there being 10 g of it in 100 g

Question 12

what causes milk to go sour?

Answer 12

lactose is oxidized to lactate by good bacteria called lactobacillus. There is an over concen of them

Question 13

describe sucrose

Answer 13

it is a oxygen glycosidic linkage between glucose and fructose
-alpha-D-glucopyranosyl (alpha 1 -> beta 2) B-D-fructofuranose

• head to head type of linkage so that would make it a non reducing disaccharides because both of the anomeric carbons are involved
• found in table sugar

Question 14

describe maltose

Answer 14

it is an oxygen glycosidic linkage between alpha 1 and alpha 4 of glucose molecules

• it is malt sugar and is used in beer productions
• because of its head to tail linkage, it is reducing
• overall: alpha-D-glucopyranosyl (1->4) alpha-D-glucopyranose

Question 15

describe lactulose

Answer 15

it is an oxygen glycosidic linkage between beta 1 of galactose and beta 4 of fructose
-overall: B-D-galactopyranosyl (beta 1-> beta 4) B-D- fructfuranose
-used as a laxative due to it being a nonabsorbable sugar which causes it to retain water
-

Question 16

what happens when milk is warmed

Answer 16

lactose is converted into lactulose

Question 17

describe trehalose

Answer 17

it has a glycosidic linkage between alpha 1 and alpha 1 of glucose causing there to be a head to head collusion

• nonreducing disaccharide
• able to retain water in shrimps and insects
• overall: alpha-D-glucopyranosyl (alpha 1 -> alpha 1) alpha-D-glucopyranose

Question 18

reducing vs non reducing disacharides

Answer 18

non reducing means that both the anomeric carbons are involved in the glycosidic linkage SO NOTHING CAN PARTICIPATE IN REDUCTION.

reducing means that only one of the anomeric carbons are involved so the other one CAN PARTICIPATE in REDUCTION

Question 19

name the two classifications of homoglycans

Answer 19

storage and structural

Question 20

why can homoglycans form linear and branched?

Answer 20

there polyhydroxy allows them to form glycosidic lnkages on the same monosacharide

Question 21

what are the fuel storage homoglycans?

Answer 21

starch and glycogen

Question 22

what are the structural component of homoglycans?

Answer 22

cellulose and chitin

Question 23

what is starch made up of?

Answer 23

linear amylose and branched amylopectin

Question 24

describe starch

Answer 24

it is used as a energy reservoir for plants especially in chloroplasts

Question 25

describe amylose

Answer 25

repetitive alpha-D-glucose at the alpha 1-4 linkage bond

Question 26

describe amylopectin

Answer 26

has linears of amylose and branched glucose of alpha 1 to 6 by every 30 monomers

Question 27

describe glycogen

Answer 27

has glycosidic linkage of glucose from alpha 1-> 6 but is branched every 10 residues

• fuel storage for animals
• 10% w/w of liver and muscles

Question 28

what is the most abundant polymer?

Answer 28

cellulose

Question 29

describe cellulose

Answer 29

it is comprised of beta d glucose and it is linear with extended sheets and is found in plant cell walls

-beta 1-4

Question 30

chitin

Answer 30

it has N-acetyl-B-d-glucosamine and is linear but with extended sheets at Beta 1-4
found in exoskeletons like crabs

Question 31

what is the second most abundant polymer?

Answer 31

chitin