What is Cork or Bark of the Tree
Cork is the strip of Secondary Meristem which replaces the epidermis of older stem of the tree.
Characteristics of cork are as follow
- It is the outer protective tissue of older stem and roots.
- Cells of cork are dead, compactly arranged and have no intercellular spaces.
- It forms bark of the tree, which is several layers thick.
- A Chemical called Suberin is present in their walls.
- Suberin makes it impervious to gases and water.
- Cork is formed by secondary Lateral Meristem called cork cambium.
- The mature cork becomes dead and filled with tannin, resin.
Formation of cork
- As plant grows older, the outer protective tissue undergoes certain changes.
- A strip of Secondary Meristem replaces the epidermis of stem.
- Cells on the outside are cut off from this epidermal layer.
- This form several layer thick cork or bark with no intercellular spaces.
Role or function of cork
- It prevents loss of water by evaporation.
- It protects plants from invasion of parasites and other harmful microorganisms.
- It provides extra insulation and protection to the plant.