[OLD] Biological Molecules - Carbohydrates

Question 1

What are monosaccharides?

Answer 1

single sugars

Question 2

what are disaccharides?

Answer 2

2 sugars bound to each other

Question 3

Are monosaccharides or disaccharides soluble and sweet tasting

Answer 3

Both

Question 4

What are polysaccharides?

Answer 4

Many monosaccharides bound to each other?

Question 5

Are polysaccharides soluble or insoluble?

Answer 5

Insoluble

Question 6

Are polysaccharides sweet tasting?

Answer 6

No

Question 7

2 examples of polysaccharides

Answer 7

starch and cellulose

Question 8

2 examples of monosaccharides or disaccharides

Answer 8

glucose and maltose

Question 9

how many carbons does glucose contain in its structure?

Answer 9

6

Question 10

is glucose a monosaccharide of a disaccharide?

Answer 10

Monosaccharide

Question 11

How are the carbons in glucose arranged?

Answer 11

Into a ring

Question 12

What are isomers?

Answer 12

the same molecules but with their atoms arranged in a different structure

Question 13

How many isomers can glucose exist as?

Answer 13

2

Question 14

Describe the alpha glucose isomer

Answer 14

carbon number 1 in the ring has an H group above the ring and an OH group below the ring

Question 15

Describe the beta glucose isomer

Answer 15

carbon number 1 in the ring has an OH group above the ring and an H group below the ring

Question 16

which carbons do bonds form between when glucose molecules bind to each other to form a polysaccharide?

Answer 16

1 and 4

Question 17

Why does a chain of beta glucoses have every other molecule rotated ‘upside down’?

Answer 17

because the OH groups are on opposite sides of the ring between a carbon 4 and carbon 1, then second molecule must turn upside down in order to line up the 2 OH groups

Question 18

What is maltose?

Answer 18

a disaccharide formed by 2 alpha glucose molecules binding to each other

Question 19

What is the bond in maltose?

Answer 19

an alpha 1, 4 glycosidic bond

Question 20

What reaction makes the bond in maltose?

Answer 20

A condensation reaction

Question 21

How is the bond formed in maltose?

Answer 21

Between two OH groups. H2O is lost and the 2 glucoses join through the remaining O

Question 22

Which 2 molecules does starch consist of?

Answer 22

amylose and amylopectin

Question 23

describe amylose

Answer 23

a straight chain of alpha glucose joined by alpha 1, 4 glycosidic bonds coiled into a spiral

Question 24

describe amylopectin

Answer 24

branched chains of alpha glucose joined by alpha 1, 4 glycosidic bonds but with 1, 6 glycosidic bonds wherever there is a side chain formed

Question 25

What is starch the energy reserve in?

Answer 25

plants

Question 26

why cannot glucose be stored in plants?

Answer 26

it is soluble and would affect osmotic balance of cells

Question 27

What is glycogen the energy reserve in?

Answer 27

animals

Question 28

Describe the structural shape of glycogen

Answer 28

Highly branched

Question 29

Why does glycogen have a lot of branches?

Answer 29

so there are lots of terminal glucose molecules that can be removed by enzymes at the same time i.e rapid release of glucose possible

Question 30

where is glycogen stored and what for?

Answer 30

in the muscles or liver for sudden movement or maintain blood sugar levels through actions of glucagon and insulin.

Question 31

What is the structural shape of cellulose?

Answer 31

Linear, unbranched, long, straight chains (where every other monomer is inverted)

Question 32

what is cellulose used for?

Answer 32

as a structural polysaccharide used in plant cell walls

Question 33

Why can't we digest cellulose?

Answer 33

We do not have enzymes with an active site complementary to the shape of a beta glucose molecule

Question 34

How does cellulose go through our digestive tracts?

Answer 34

as fibre

Question 35

3 ways in which starch molecules may be different from each other

Answer 35

Different numbers of glucose Different proportions of amylose/amylopectin Different number of branches / branches in different places

Question 36

How is the structure of cellulose linked to its function?

Answer 36

Hydrogen bonds for strength and rigidity in plant cells

Question 37

Monomer used in starch

Answer 37

Alpha glucose

Question 38

Is starch found in plants or animals?

Answer 38

Plants

Question 39

What are the types of bonds found in starch?

Answer 39

Amylose - alpha 1, 4 glycosidic | Amylopectin - alpha 1, 4 glycosidic and 1, 6 branches

Question 40

What is the structural shape of starch?

Answer 40

Amylose - long unbranched chain coiled into a spiral by hydrogen bonds Amylopectin - branched chain

Question 41

What is the function of starch?

Answer 41

Storage of energy

Question 42

How does the structure of starch and glycogen relate to their function?

Answer 42

Insoluble so osmotically inactive Folded to make a compact shape Large molecule too big to cross membranes Easily hydrolysed to release glucose

Question 43

Monomer used in glycogen

Answer 43

Alpha glucose

Question 44

Is glycogen found in plants or animals?

Answer 44

Animals

Question 45

What is the type of bond found in glycogen?

Answer 45

Alpha 1, 4 glycosidic bonds with 1, 6 glycosidic bonds

Question 46

What is the function of glycogen?

Answer 46

Storage of energy

Question 47

Monomer used in cellulose

Answer 47

Beta glucose

Question 48

Is cellulose found in animals or plants?

Answer 48

Plants

Question 49

What type of bond is found in cellulose?

Answer 49

Beta 1, 4 glycosidic

Question 50

How does the structure of cellulose relate to its function?

Answer 50

Insoluble Fully permeable to dissolved substances Hydrogen bonds between cellulose strands gives strength Alternate bonding makes cellulose molecules very straight Fibres are criss-crossed in cell walls making them resistant to stretching in any direction