sugars

Question 1

what is the structure of heparin

Answer 1

oligosaccharide

Question 2

what is heparin?

Answer 2

anticoagulant

Question 3

give examples of monomers

Answer 3

glucose
fructose
galactose
mannose

Question 4

how can you modify sugars?

Answer 4

replace the OH group with an amine, phosphate or sulphate

remove the OH group

Question 5

give an example of a sugar phosphate and how its made

Answer 5

glucose 6-phosphate

phosphorylation of glucose using ATP

Question 6

name some sulphated sugars

Answer 6

chondroitin sulfate
heparan sulfate
dermatan sulfate

Question 7

what enzyme makes sulphated sugars?

Answer 7

sulpho-transferase

Question 8

what is the role of sulphated sugars?

Answer 8

ECM - negative so they can hold water

lubricants and shock absorbers

Question 9

what catalyses the formation of a glycosidic bond?

Answer 9

glycosyl transferase

Question 10

what enzymes are used to break glycosidic bonds?

Answer 10

hydrolases

Question 11

describe the structure of glycogen

Answer 11

alpha glucose
main chain is a-1,4
side chains are a-1,6

Question 12

what is the role of glycogen

Answer 12

energy store in liver and muscles

broken down by glycogen phosphorylase

Question 13

name disaccharides and what they’re made up of?

Answer 13

• Maltose (Glc-Glc)
• Sucrose (Glc-Fru)
• Lactose (Gal-Glc)

Question 14

what bond is in disaccharides?

Answer 14

glycosidic bond

Question 15

what are oligosaccharides?

Answer 15

3-10 monosaccharides

Question 16

what are blood group antigens?

Answer 16

oligosaccharides

Question 17

what are enantiomers?

Answer 17

Pair of isomers that are (non-superimposable) mirror images

Question 18

what is the D and L form of enantiomers?

Answer 18

• D-form: OH group attached to the right of the asymmetric carbon
• L-form: OH groups attached to the left of the asymmetric carbon

Question 19

can D glucose be digested?

Answer 19

yes

Question 20

what is L glucose used for?

Answer 20

laxative

used in no calorie foods

Question 21

what are the 2 stereoisomers of glucose and which is more stable?

Answer 21

alpha and beta

beta is more stable

Question 22

how does glucose form a ring structure?

Answer 22

OH on C5 reacts with the aldehyde/ketone group

Question 23

how can sugars be modified?

Answer 23

OH group replaced with
• Amine (NH2) = amino sugars
• Sulphate (SO4) = sulphated sugars
• Phosphate (PO4) = phosphorylated sugars
• Removal of OH = deoxy sugar

Question 24

what enzyme makes sulphated sugars?

Answer 24

sulpho-transferase

Question 25

how are sugar sulfates used?

Answer 25

as GAGs in the ECM e.g. chondroitin sulphate Heparan sulphate Dermatan sulphate also as lubricant or shock absorber give structure to connective tissue

Question 26

what type of reaction is the formation of a glycosidic bond?

Answer 26

dehydration/condensation

Question 27

what catalyses the formation of glycosidic bonds?

Answer 27

glycosyl transferase

Question 28

what will the glycosyl enzyme differ according to?

Answer 28

D or L form alpha or beta anomer location of OH group type of bond

Question 29

what is the breakdown of a glycosidic bond?

Answer 29

hydrolysis

Question 30

what enzymes carry out hydrolysis?

Answer 30

hydrolases

Question 31

what is glycogen?

Answer 31

polymer of glucose

Question 32

describe the structure of glycogen?

Answer 32

main chain has glycosidic bonds - alpha 1,4 side chains have beta 1,6 chains

Question 33

describe the structure of amylose?

Answer 33

straight chain with alpha 1,4 links

Question 34

what is the subunit of glycogen?

Answer 34

alpha glucose

Question 35

what is the subunit of cellulose?

Answer 35

beta glucose

Question 36

what is the subunit of starch?

Answer 36

alpha glucose

Question 37

does cellulose have branches?

Answer 37

no