EFFECTS OF OSMOSIS ON CELLS WHEN PLACED IN DIFFERENT SOLUTIONS

SOLUTION TYPE Concentration of dissolved substances

(solutes)

Concentration Gradient Results in Animal Cells Results in Plant Cells
ISOTONIC Same as the living cell Zero No change No Change
HYPOTONIC Lower than the living cell Net water movement into the cell Cell swells and bursts ** Pressure created by excess water stored in central vacuole
HYPERTONIC Higher than the living cell Net water movement out of the cell Cell shrinks

* plasmolysis

Central vacuole collapses and plasmolysis occurs

* Plasmolysis - The shrinkage of cytoplasm resulting from loss of water by osmosis, in a cell placed in a hypertonic solution.

** Turgor Pressure - In plant cells, the pressure on the cell wall that results because of the influx of water in osmosis.

LAB DIAGRAM

Demonstration of celery in hypotonic and hypertonic solutions

                               

Celery before it was placed in distilled water.                       Celery before it was placed in salt water   

- somewhat limp and soft                                                     - firm and in good shape     

 

                                                                                                                                                                               

  Celery after standing in distilled water for 4 hours        Celery after standing in salt water after 4 hours        

 - absorbed the water and was very stiff  and rigid             - the bottom 1/4 has turned very soft and mushy

                                              

            - hypotonic solution                                                            - hypertonic solution

                                                     

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