STOMATA in Plants


 STOMATA:

Stomata is a small longitudinal pore resent on the epidermal layer of cells in plants.
 
Stomata helps in exchange of gases in plant cells. It helps in respiration in plants.

The whole structure of stomata consist of two guard cells which is surrounded by Subsidiary cells or Accessory cells. Subsidiary cells are specialised parenchymatous thick walled epidermal cells surrouding the Guard cells.

 

In Dicots the Guard cells are kidney shape or bean shape.
stomata in plants

In Monocots, the shape of Guard cells is Dumble shape.

The dorsal wall of guard cells are thin and elastic in nature.
The ventral wall of guard cell is non-elastic and thick.
 


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