Cork Cambium

• Cork Cambium is also known as Phellogen.
• The cork cambium is a secondary lateral meristem and it is responsible for secondary growth that replaces an epidermis in roots and stems.

Reason:

• This is formed due to vascular cambium activity inside the stem and root.
• This leads to the outer cortical and epidermis layers getting broken and need to be replaced by new protective cell layers.

Structure:

• Cork cambium is formed in the cortex region.
• It is a couple of layers (double layer) and made up of narrow, thin walled and nearly rectangular cells.
• It produces cells towards the inner side, that cells are known as secondary cortex or phelloderm.
• It produces cells on their outer surface, that cells are known as phellem or cork.
• Phellem (Cork), Phellogen (cork cambium) and phelloderm (secondary cortex) together are called periderm.

Functions:

• Phelloderm helps in photosynthesis and stores food materials.
• Phellogen is a synthesis of Phelloderm (new cells towards inner cortex) and Phellem (new cells towards outer epidermis).
• Phellem is impervious to water due to suberin deposition in the cell wall.