Each cell has a thick transparent shell with a thin areas - pores that can be discerned only under high magnification. The composition of membranes of plant cells is a special substance - cellulose, which gives them strength. Inside is a colorless viscous substance - Cytoplasm (from the Greek words "kitos" - a vessel and "plasma" - education). With strong heating and freezing it is destroyed, and then the cell dies. The cytoplasm is a small dense core, which can be distinguished nucleolus.
Using an electron microscope revealed that the cell nucleus has a very complicated structure. Almost all cells, especially in older, well marked cavity - the vacuole (from the Latin word "vakuus" - empty). They filled with cell sap - water with dissolved sugar in it and other organic and inorganic substances. By cutting the ripe fruit, or another part of the succulent plant, we corrupt the cells and their vacuoles follows from the juice. In the cell sap may contain coloring agents (pigments), giving the blue, violet, raspberry colored petals and other parts of plants, and autumn leaves. Preparing and viewing of the preparation of skin scales onion under a microscope 1. Consider the figure 5, the sequence of the drug preparation peel of onion scales. 2. Prepare a glass slide, carefully wiping his gauze. 3. Pipette, apply 1-2 drops of water on a glass slide. 4. With a dissecting needle, carefully remove a small piece of transparent skin from the inside surface of onion scales.
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