Polymers Of Glucose

Question 1

What are the 3 main polymers of glucose

Answer 1

Starch,glycogen, cellulose

Question 2

Structure of starch

Answer 2

2 alpha molecules joined by glycosidic bond

Bonds are further stabilised by H bonds

Question 3

Describe the structure of 2 particular starches

Answer 3

Amylose- formed by c1-c4 glycosidic bonds between alpha particle. Is a disaccharide
amylopectin - made by c1-c4 glycosidic bond and once every 25 a c1-c6 bond causing a twist

Question 4

Properties of starch

Answer 4

In plant cells glucose made by photosynthesis is stored as starch
H bonds make polysaccharide more compact and therefore less soluble

Question 5

Functions of starch

Answer 5

Glucose made by photosynthesis in plant cells is stored as starch which is very compact, due to h bonds, and easy to release sugar
It is a chemical energy store
Your body digests starch to make glucose
Insoluble in water

Question 6

Structure of cellulose

Molecules

Answer 6

for 2 beta molecules to join together alternate beta glucose molecules are turned upside down
This creates the c1,c4 glycosidic bond

Question 7

Properties of cellulose

Answer 7

Is unable to coil or form branches which means glucose cannot be transferred quickly
Cellulose molecules make H bonds with each other forming microfibrils, which form macrofibrils, which form fibres

Question 8

Functions of cellulose

Answer 8

Cellulose is an important part of the human digestive system as it is extremely hard to breakdown into its monomers
Forms the “fibre” or “roughage” necessary for a healthy digestive system

Question 9

Structure of glycogen

Answer 9

C1, c4 glycosidic bond formed by alpha molecules
%10 c1,c6
Angels of the bond meaning a long chain of glucose twists to form a helix which is stabilised by H bonds

Question 10

Glycogen properties

Answer 10

Joined tighter by glycosidic bonds
H bonds
Similar to amylopectin however more extensive branches maxing it more compact

Question 11

Functions of glycogen

Answer 11

Glucose is stored as glycogen
This is an energy storage material known as glycogen in animals and fungi
Can be broken down and released into the blood steam when body is low on sugar
Reserved for synthesis of ATP during muscle contraction

Question 12

Differences between cellulose and amylose

Answer 12

Amylose - coiled , alpha molecules, 1-4 glycosidic bonds , granular, molecules in same orientation
Cellulose- no coiled , beta molecules, c1-4 glycosidic bond, fibrous, 180 degree rotation

Question 13

Disaccharide formation

Answer 13

Formed when 2 monosaccharides units join forming a glycosidic bond, by a condensation reaction

Question 14

What happens during a condensation reaction of disaccharides

Answer 14

2 hydrogen and 1 oxygen atom join forming a water molecule

Oxygen is bound between c1 and c4

Question 15

Difference between hexose and pentose

Answer 15

Glucose - 4 ( oh-c-h ), 1c - ch2oh, 1 (O=c-h)

Ribose - 3 ( h-c-oh), (h-c-h-oh), h-c=o

Question 16

Hydrolysis reactions

Answer 16

Requires the addition of water molecules

Reactions are catalysed by enzymes

Question 17

What are trigceride and phospholipids

Answer 17

Macromolecules

Question 18

Explain why starch is a good way to store glucose

Answer 18

Contains amylopectin which is branched
Consists of long stands and branches therefore can store lots of glucose, meaning more energy
Very compact due to branching
Branched ends means glucose can be transferred quickly

Question 19

How is glucose molecule suited to its function

Answer 19

Soluble so can be transported easily
Small so can diffuse across membranes
Can be broken down quickly for ATP use
Molecules can join to form polysaccharides and be stored for later use

Question 20

Why when making beta chains must alternate molecues be flipped

Answer 20

To allow combination of hydroxyl groups which if they were not flipped would not be aligned