SXConline
Study of Plant Cells
Geranium

Objective:


1. To develop and understanding about arrangement of cells.
2. To study about shape and size of different type of cell.
3. To study the internal organization of different typer of cells.


REQUIREMENT:
Apparatus: compound microscope, watch glass, slide, coverslip, forceps, scissors, brush, blotting paper, needle etc.
Materials: Geranium leaf
Chemicals: dilute sefranine, Glycerine


PROCEDURE:
(i) Peeling: A wet geranium leaf was taken, its epidermal layer was peeled out in wet condition and was placed into watch glass
containing water.
(ii) Staining: The peeled layer was cut into small rectangular pieces and one of the finely cut pieces was stained on a watch glass with the
help of dilute sefranine for about 20-30 seconds. Then excess of sefranine was washed with water.
(iii) Mounting: 2 or 3 drops of dilute glycerine was dropped at the centre of the slide and then stained leaf material was dropped over it, by using brush. The material was spread properly with the help of brush and needle to avoid folding. Then it was covered by a clean and dry cover slip without trapping any air bubbles.
The prepared slide was observed in low and high power of microscope.



Microscopic observation:
i) The cells was compactly arranged without any intercellular spaces. They were arranged like zigsaw puzzle. The guard cell always appeared
in pair with a small hole between them called stomata. A set of guard cells were surrounded by 5-4 normal epidermal cells. A number of
needle like hairs were arising from various places.
ii) The normal epidermal cells were of irregular (amoeboid) shapes. The guard cells were bean shaped. The elongated hair contained many
rectangular hair cells.
iii) The normal cells were of irregular sizes. The guard cells were of similar sizes, rether smaller than the normal cells. The cells on the
hair were the smallest on the decreasing order from the base to the top.
iv) Different parts of the cells: As like any other plant cells, the cells were bounded by a rizid cellwall. In between the cellwalls of two
cells, a cementing layer called middle lamella was present. Inner to the cellwall lied a cell membrane surrounding cytoplasm, The
cellwall of the guard cells was thicker on the inner side of cellwall. Large and irregular vacuole was present at the centre. A dense nucleus
was located in the faintly granular cytoplasm at the periphery. Numerous chloroplasts could be seen in the guard cells.

View the Figure for this Practical