Glycobiology

Question 1

3 functions of glycoproteins:

Answer 1

blood clotting, reproduction and immune system recognition

Question 2

functions of carbohydrates:

Answer 2

energy sources, energy storage, structural component of cell membranes (bacterial cell walls), nucleotide biosynthesis (ribose + deoxyribose), lipid biosynthesis (acetyl coA)

Question 3

monosaccharide formula:

Answer 3

Cn(H2O)n
same number of oxygens as there are carbons

Question 4

aldose?

Answer 4

has an aldehyde group on an end carbon

Question 5

ketose?

Answer 5

has a ketone group on one of the middle group

Question 6

when can monosaccharides become cyclic?

Answer 6

when there are more than five carbons

Question 7

pyranose?

Answer 7

6-membered ring
5 carbon and one oxygen

Question 8

furanose?

Answer 8

5-membered ring
4 carbon and one oxygen

Question 9

what isomer is glucose of galactose?

Answer 9

stereoisomer

Question 10

what isomer is fructose of glucose/galactose?

Answer 10

structural - different structural arrangement

Question 11

lactose intolerant?

Answer 11

mutation in the lactase gene

Question 12

homopolysaccharides?

Answer 12

contain only a single type of monosaccharide

Question 13

heteropolysaccharides?

Answer 13

contain two or more different kinds of monosaccharide

Question 14

Glycogen is branched - what are the glycosidic bonds that cause this branching?

Answer 14

a 1,4 glycosidic bonds
a 1,6 glycosidic bonds

Question 15

what enzyme hydrolyses a1,4 glycosidic bonds in glycogen?

Answer 15

glycogen phosphorylase

Question 16

what enzyme hydrolyses a1,6 glycosidic bonds in glycogen?

Answer 16

debranching enzyme

Question 17

where is excess glucose stored as in plants?

Answer 17

roots and seeds

Question 18

During fermentation, what three volatile fatty acids do we start with?

Answer 18

acetate, butyrate, propionate

Question 19

N-acetyl-D-glucosamine?

Answer 19

chitin

Question 20

where is chitin found?

Answer 20

in the exoskeletons of inverterbrates

Question 21

what is the process that results in glucose being formed from pyruvate?

Answer 21

gluconeogenesis

Question 22

proteoglycans?

Answer 22

carbohydrates modified with a carbohydrate component

Question 23

endotoxin AKA?

Answer 23

lipo-polysaccharide

Question 24

where can glycoproteins be found?

Answer 24

extracellular matrix, outer face of the plasma membrane and in the blood

Question 25

eCG

Answer 25

equine chorionic gonadotropin

Question 26

EPO

Answer 26

erythropoietin

Question 27

what does the basic proteoglycan unit consist of?

Answer 27

a core protein with covalently attached glycosaminoglycans

Question 28

give an example of a glycosaminoglycans?

Answer 28

heparin

Question 29

what is heparin?

Answer 29

an anticoagulant

Question 30

what sort of disorders might require treatment from heparin?

Answer 30

cardiac/aortic/arterial thrombosis
pulmonary thrombosis and thromboembolism
disseminated intravascualr coagulation

Question 31

what is aggrecan?

Answer 31

a proteoglycan, it is a major component of cartilage

Question 32

describe the difference between the alpha and beta ring structures:

Answer 32

a - newly formed OH group on the opposite sides from the CH2OH (below the ring)
b - newly formed OH group on same sides as the CH2OH (above the ring)

Question 33

what is the anomeric carbon within the Haworth projection of a cyclic monosaccharide?

Answer 33

the one that has a centre of chirality and is bonded to the ‘deciding’ OH group