Procedure

Microscopic study of cells in a plant stem involves a series of steps to prepare, stain, and examine the cells under a microscope.

Equipment Required:

• Fresh plant stem (e.g. Amaranthus)
• Single edged sharp new blades
• Microscope slides
• cover slips
• Beaker
• Distilled water
• Watch glass
• Stains (e.g., safranin, fast green, iodine)
• Dissecting needle
• Forceps
• Dropper
• Light microscope
• Distilled water
• Blotting paper

Sample collection:

1. Choose a fresh stem of a plant.

Sample Preparation:

1. Cut the stem from the selected plant
2. Use a single edge blade to cut the stem transversely.
3. Hold the stem material between your thumb and index finger, such that the blade edge is parallel to the leaf’s longitudinal axis. Make very thin slices
4. Using the edge of the blade, transfer these slices that carry the thin leaf section with the help of a brush into watch glass containing water. This helps maintain turgidity and prevents wilting during the observation.

Staining & Mounting:

1. Use a pair of fine-pointed forceps to transfer the stem section onto a glass microscope slide.
2. Add 2- 3 drops solution of safranin for 2-5 minutes. Safranin stains lignified and cutinized cell walls red.
3. Rinse the sections briefly in distilled water to remove excess safranin.
4. Add fast green for a few seconds to a minute. Fast green stains cellulose cell walls green.
5. Rinse the section in distilled water.
6. Add a drop of water to the leaf section to prevent drying out and to create a wet mount.
7. Carefully place a coverslip over the stem section, using a needle to gently lower it to and avoid trapping air bubbles.

Microscope Setup:

1. Place the prepared slide on the stage of the simple microscope.
2. Observe the section by turning the lowest magnification objective lens (usually 4x or 10x) and bring the sample into focus using the coarse and fine adjustment knobs.
3. Once the sample is roughly in focus, switch to higher magnification objective lens (40x) to observe finer details of the internal cells of the stem.

Observation:

1. Move the slide around using the stage controls to explore different regions of the leaf section.
2. Observe various structures such as epidermis, cambium, pith cells etc.
3. Take note of cell shape, size, arrangement, and any distinct features like chloroplasts or cell walls.