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Draw a labelled diagram of stomata. Write two functions of stomata.


In the epidermis of the leaves, special bean-shaped cells called guard cells are present. When the guard cells are tight/turgid(Like a water-filled balloon) a pore appears between them. This pore is stoma. Conversely, when the guard cells become loose, they lie against one another and the stoma closes.


  • These are the sites of gaseous exchange. Carbon dioxide needed by the plant for photosynthesis enters through the stomata.
  • Stomata are also involved in transpiration (Loss of water by evaporation from leaf surface that provides a cooling effect)
  • Oxygen produced in photosynthesis also leaves the plant via stoma.

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