Q. What are the values of DPD for plant cells under hypertonic, hypotonic and isotonic media?
In plant cells under hypertonic medium there is loss of water for the external, SF > 0 the vacuolar pressure is high as it is concentrated and TP = 0 there is no distension of the cell wall since the cellular volume is reduced as a result DPD = SF. These cells are known as plasmolysed cells, situation characterized by the retraction of the cell membrane that detach from the cell wall.
In plant cells under isotonic medium there is no raise of the internal water volume, SF > 0 and TP = 0 since the cell wall is not distended. The cell membrane slightly touches the cell wall and in this situation the cell is known as a flaccid cell. In plant cells under hypotonic medium there is tendency of water to enter, SF = TP since the osmotic pressure is totally compensated by the distension of the DPD = 0and cell wall. The cell that has expanded itself to this point is known as a turgid cell.