Startch, Cellulose, Glycogen

Question 1

Describe how the structure of glycogen is related to its function.

Answer 1

1. Branched so compact so more in a small space
2. Polymer of glucose so easily hydrolysed
3. Branched so more ends for faster hydrolysis
4. Glucose polymer so provides respiratory substrate for energy
5. Insoluble so does not affect water potential

Question 2

Describe how the structure of startch is related to its function.

Answer 2

1. Compact so lots can be stored in a small space
2. Insoluble so doesn’t affect water potential
3. Highly branched so more ends for faster hydrolysis
4. Provide respiratory substrate for energy

Question 3

Describe how the structure of cellulose is related to its function.

Answer 3

1. Hydrogen bonds across parallel chains of beta glucose which provide strength
2. Insoluble so won’t affect water potential
3. Molecules grouped to form microfibrils which are group to form fibres which provides strength.

Question 4

Describe three differences between the structure of cellulose and glycogen.

Answer 4

1. Cellulose is made of beta glucose whereas glycogen is made of alpha glucose.
2. Cellulose has straight chains whereas glycogen is branched
3. Cellulose has 1-4 glycosidic bonds whereas glycogen has 1-4 and 1-6 glycosidic bonds.

Question 5

Where is startch, cellulose and glycogen found?

Answer 5

Startch- Plant cells
Cellulose -Plant cell walls
Glycogen - Animals (muscles and liver) and bacteria