Cellulose

Question 1

How is cellulose formed?

Answer 1

Cellulose is formed from condensation reactions between many glucose molecules. It forms linear unbranched chains.

Question 2

What is the orientation of the -OH group on carbon 1?

Answer 2

The -OH (hydroxyl) group on carbon 1 is above the plane of the ring of carbon atoms.

Question 3

What is the orientation of the -OH group on carbon 4?

Answer 3

The -OH (hydroxyl) group on carbon 4 is below the plane of the ring. As a result, alternate glucose molecules are rotated 180° to form glycosidic bonds (1-4).

Question 4

How are parallel chains of cellulose connected?

Answer 4

Parallel chains are cross-linked by hydrogen bonds to form microfibrils. These microfibrils form bundles called fibers.

Question 5

What is the function of fibres in plant cells?

Answer 5

Fibres have high tensile strength and form basis for plant cell wall

Fibres provide structural support for plant cells.

Question 6

How does the cell wall prevent plant cells from bursting?

Answer 6

The pressure created by the cell wall stops too much water entering by osmosis and prevents cell lysis

This process provides support for plant tissues.