Explain how the bark of the tree is formed? How does it act as protective tissue?

Hi,

Bark is the outermost covering of stems and roots of old plants. It includes dead as well as some living part of plant stem. It is used as wood. It consists of cork (dead outermost protective tissue of older stem), cork cambium, cortex and phloem. Cork cambium or phellogen develops in the cortex region.

Bark is formed as a result of the secondary growth in the plants. Phallogen cut the cell inside as phelloderm or secondary cortex and outer side as phellem of cork.

The bark is a water proof protective layer (bark) present on the trees to prevent loss of water through evaporation.

Since it is majorly consists of dead cell, it forms a rigid covering that protects the interior of the plant from the entry of harmful micro-organisms, mechanical injury, high temperature, etc.