Procedures:

Using the tweezers, remove the epidermis (thin layer) from the cataphyll (skin). Make a longitudinal section. Make the same section in one of the halves of the onion and remove the skin (figures 1a and 1b);

Put one drop of water over the slide (figure 1c);

Put the epidermis over the drop of water on the slide (figure 1d);

Instill one drop of stain over the epidermis (methylene blue was used, figure 1e);

Place the cover slip over the epidermis (figures 1f and 1g);

Look in the microscope in different magnification grades (figure 1h);

Magnification grades used: Ocular 5 X with 40/0.1 – 160/0.17 and 10/025 – 160/0.17 Objective Lens.

Occurrence:

The stain highlights the material under observation.

Conclusion:

Elongated cells are observed, limited by cell walls;

The cytosol is delimited by cell sap vacuole (space that is apparently empty) nucleus.

Note: If necessary, this experiment may be conducted only with water drop over the slide, the epidermis over the water and the cover slip over the epidermis. In this case, certain details are lost.

In a good preparation, it is possible to see the nucleus with two nucleolus.