List the characteristics of cork. How are they formed? Mention their role.

Characteristics 

(a) 

= Cells of cork are dead at maturity 

= These cells are compactly arranged 

= Cells do not possess intercellular spaces. 

= Cells possess a chemical substances suberin in their walls 

= They are several layers thick. 

(b) As plants grow older, a strip of secondary meristem replaces the epidermis of the stem. Cells cut on the outer side by this meristem are called cork. 

(c) They are protective in function for older stem/twigs/branches. They are impervious to gases and water.

1. Cork is outer protective tissue of older stems and roots.
2. Cells of cork become dead on maturity and contain resins , tannins and air
3. Cork is a compact tissue without intercellular spaces.
4. Cells of cork are rectangular in shape, arranged in several layers and impermeable to water due to deposition of suberin in their walls.
5. Cork is formed from secondary lateral meristem (phellogen or cork cambium)
6. (i) Functions. (i) Protection against pathogens. `" "` (ii) Prevent loss of water by evaporation.
(iii) Protection against mechanical injury to plant parts. `" "` (iv) Has lenticels for the exchange of gases.
(v) It is commercially used.