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An experiment for plasmolysis
Aim: To know how plasmolysis takes place in a cell.

Materials required:Red onion, cut into slices approximately 1 cm wide, 1 or 2
 Microscope
Microscope slides, 1 per specimen
Cover slips, 1 per specimen
Distilled water
Salt solution (sodium chloride) 5% w/v
Teat pipettes
Forceps
Pieces of filter paper.
Procedure: Take red onion cells, cut a 1 cm square of onion. Then peel off a single layer of the red cells from an inner fleshy leaf of the onion.
Place the strip on a slide. Cover it with a drop or two of distilled water. Add a cover slip.
 Look at the cells through a microscope, starting with the low power lens.

 Take another strip of cells from your plant material. This time mount the cells with a couple of drops of 5% sodium chloride solution.
 Examine through the microscope and compare the cells to those mounted with distilled water.

 After a few minutes draw out the sodium chloride solution with a piece of filter paper placed at the edge of the cover slip. Replace it with distilled water added at the other side of the cover slip.
Observation: Cells are plasmolysed (plasmolysis has occurred) when the cell contents shrink and come away from the cell wall.


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