We have made four set-ups in two different specimens. Onion and Boat of Moses skin with water, 2%, 5% and 10% salt (NaCl) Solution. Based on our experiment, the result of the set up explains that the presence of the salt solution results in outward diffusion of water and the collapse of the protoplast. In table 1, we have observed under the microscope that the onionskin mounted with water has no results of plasmolyzed cell (0%). This time, we have repeated the procedure with 2% salt solution and it is observed that there are 6 (3.9%) plasmolyzed cells. In the 5% salt solution, there are 119 (87.5%) plasmolyzed cells. And in the 10% salt solution, there are 142(100%) number of plasmolyzed cells present. In table 2,same procedure was done but with different specimen. We have observed that the boat of moses mounted with water also has no results of plasmolyzed cell (0%). In the 2% salt solution, there are about 20 (43.4%) plasmolyzed cells. 46 (88.5%). plasmolyzed cells were also observed in the set-up with 5% salt solution and in the 10% solution, all of the 59 cells are plasmolyzed (100%). Thus, increase in percentage of the salt in a solution also increases the number of the plasmolyzed cells. Water passes out of the cell towards a region of lesser water concentration which results to the shrinkage of the protoplasm (Figure 1). This shrinkage away from the cell wall due to excessive loss of water is called plasmolysis.
Figure 1. Plasmolysis in Allium Cepa : The first image in the left shows that the cells mounted with water shows no signs of plasmolysis, in the middle mounted with 2% NaCl solution shows minimal shrinkage of cells, in the right most image mounted with 5% NaCl solution almost all of the cells were plasmolyzed.
After observing the onion and boat of moses skin in the different solution, we have replaced the solution with distilled water. Based on our observation, when the solution is replaced, the protoplast regained to its...
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