3.1.2 Carbohydrates

Question 1

Glycosidic bond

Answer 1

Covalent bond that joins a sugar molecule to another group. Formed by condensation reaction between 2 monosaccharides

Question 2

Maltose

Answer 2

Glucose + Glucose

Question 3

Sucrose

Answer 3

Glucose + Fructose

Question 4

Lactose

Answer 4

Glucose + Galactose

Question 5

Monosaccharides + examples

Answer 5

Monomers from which larger carbohydrates are made. Glucose, fructose, galactose

Question 6

Disaccharides + examples

Answer 6

Formed by condensation of 2 monosaccharides. Maltose, sucrose, lactose

Question 7

Describe 3 differences between the structure of a cellulose and glycogen molecule

Answer 7

C-straight chain, G-branched chain
C-beta glucose, G-alpha glucose
C-1,4 glycosidic bonds, G-1,4 + 1,6 glycosidic bonds

Question 8

Cellulose formed by

Answer 8

Condensation of beta glucose

Question 9

Draw alpha glucose

Answer 9

(Look up)

Question 10

Draw beta glucose

Answer 10

(Look up)

Question 11

Glycogen features

Answer 11

Polysaccharide made of alpha glucose monomers
Storage molecule -
compact
Insoluble- osmosis inactive
Highly branched - lots of ends can be acted on simultaneously by enzymes to form glucose for respiration

Question 12

Starch features

Answer 12

Polysaccaride made of alpha glucose monomers
Chains can be branched (many ends can be hydrolysed) or unbranched (compact)
Insoluble - osmosis inactive
Compact
Forms alpha glucose when hydrolysed for respiration

Question 13

Cellulose features

Answer 13

Polysaccharide made from beta glucose monomers
Straight unbranched chains running parallel allowing hydrogen bonds to form cross linkages
Grouped into microfibrils which form fibres for strength