1.4 cellulose

Question 1

What is the difference in structure between cellulose and starch

Answer 1

Cellulose is made up of beta glucose unlike starch and glycogen which are made up of alpha glucose

Question 2

What is the structure of cellulose

Answer 2

Cellulose has long unbranched chains and run parallel to one another allowing H-bonds to form cross linkages between adjacent chains

Question 3

Key points on structure of cellulose

Answer 3

Cellulose chain has adjacent glucose molecules rotated by 180°. This allows hydroxyl (OH-) group on adjacent parallel chains that help to give cellulose it’s structural ability

Question 4

How are microfibrils formed

Answer 4

Cellulose molecules are grouped together to form microfibrils

Question 5

How does cellulose cell prevent the cell from bursting

Answer 5

Water enters cellulose cell by osmosis. It does this by exerting an inward pressure that stops any further influx of water

Question 6

Why is it important that leaves and stems are in a turgid state

Answer 6

This is important because they can provide the maximum surface area for photosynthesis

Question 7

How does microfibrils provide more strength

Answer 7

The cellular chains form microfibrils which in turn are grouped to form fibres all of which provide more strength