Carbohydrates

Question 1

what is an organic compound?

Answer 1

a compound containing carbon

Question 2

what does a carbohydrate consist of?

Answer 2

• carbon
• hydrogen
• oxygen

Question 3

What is the general formula of carbohydrates?

Answer 3

Cx(H2O)y

Question 4

what are the 3 main groups of carbohydrates?

Answer 4

• monosaccharides
• disaccharides
• polysaccharides

Question 5

what are monosaccharides?

Answer 5

single sugar units

Question 6

What is the general formula of monosaccharides?

Answer 6

(CH2O)n

Question 7

what is the general name for monosaccharide with 3 carbons?

Answer 7

triose

Question 8

name an example of a triose

Answer 8

glyceraldehyde

Question 9

what is the general name for monosaccharide with 5 carbons?

Answer 9

pentose

Question 10

name an example of a pentose

Answer 10

ribose

Question 11

what is the general name for monosaccharide with 6 carbons?

Answer 11

hexose

Question 12

name an example of a hexose

Answer 12

glucose

Question 13

roles of monosaccharides

Answer 13

• building blocks for larger molecules

- energy source for respiration

Question 14

what is a hydroxyl group?

Answer 14

an -OH group

Question 15

where is the hydroxyl group in alpha-glucose?

Answer 15

below the plane

Question 16

where is the hydroxyl group in beta-glucose?

Answer 16

above the plane

Question 17

what are disaccharide made of?

Answer 17

two monosaccharides

Question 18

what type of reaction joins monosaccharides?

Answer 18

condensation reaction

Question 19

what is a condensation reaction?

Answer 19

making of a bond with the removal of water

Question 20

what type of bond is formed?

Answer 20

glycosidic bond

Question 21

what is the reaction controlled by?

Answer 21

enzymes

Question 22

what type of reaction can break down the disaccharides into monosaccharides?

Answer 22

hydrolysis

breaking of a bond with the addition of water

Question 23

what disaccharide is formed from alpha-glucose + alpha-glucose?

Answer 23

maltose

Question 24

what disaccharide is formed from alpha-glucose + galactose?

Answer 24

lactose

Question 25

what disaccharide is formed from alpha-glucose + fructose?

Answer 25

sucrose

Question 26

what are polysaccharides?

Answer 26

polymers

Question 27

name 3 polymers of glucose

Answer 27

• starch
• glycogen
• cellulose

Question 28

what is the role of starch in plants?

Answer 28

long-term energy storage

Question 29

why is glucose not used for storage?

Answer 29

• soluble: affects osmosis

- reactive: affects normal cell chemistry-

Question 30

why is starch useful for storage?

Answer 30

• soluble - does not affect osmosis
• inert: chemically unreactive
• compact/convenient

Question 31

what alpha-glucose polymers does starch consist of?

Answer 31

• amylose

- amylopectin

Question 32

what is ratio of amylose: amylopectin?

Answer 32

30%:70%

Question 33

what is the role of glycogen in animals?

Answer 33

long-term energy storage

Question 34

what are granules and where are they found?

Answer 34

• clusters of glycogen

- found in liver and skeletal muscles

Question 35

what monomer is cellulose made of?

Answer 35

beta-glucose

Question 36

what are the roles of cellulose?

Answer 36

• provide rigidity
• makes cell turgid by exerting inward pressure on cell wall to stop influx of water
• also useful for photosynthesis because turgidity means maximum SA for photosynthesis

Question 37

what type of chains does cellulose form?

Answer 37

straight, unbranched chains

Question 38

what connects parallel chains?

Answer 38

hydrogen bonding

Question 39

why is cellulose strong?

Answer 39

chains of beta-glucose form microfibrils which are held together in fibres

Question 40

why are successive beta-glucose monomers rotated 180 degrees?

Answer 40

so that hydroxyl groups can be next to each other so that condensation reaction can take place to form glycosidic bonds