Class 9 Biology - Study of Plant Tissues

Aim

To study different types of plant tissues under a microscope and understand their structure and function.

Materials Required

• Microscope
• Glass slide
• Cover slip
• Water
• Leaf peel (e.g., Rhoeo leaf or Tradescantia leaf for epidermal tissue study)
• Stain (safranin or iodine solution for better visibility of tissues)

Image Reference

Procedure

1. Using forceps, peel a thin layer from the lower epidermis of a leaf (e.g., Rhoeo or Tradescantia leaf).
2. Place the peel in a drop of water on a clean glass slide to prevent it from drying out.
3. Add a drop of stain (e.g., safranin) to the peel and allow it to sit for 1-2 minutes to enhance the visibility of cell structures.
4. Gently place a cover slip over the sample to avoid trapping air bubbles.
5. Place the slide under the microscope. Begin with the lowest magnification lens to locate the tissues, then switch to higher magnifications for a detailed view.
6. Observe the different types of tissues like the epidermis, stomata, xylem, and phloem in the leaf peel.

Observation

Under the microscope, the following tissues can be identified:

• Epidermis: A single layer of cells forming the outermost boundary of the leaf. The cells are rectangular and tightly packed.
• Stomata: Small openings in the epidermis surrounded by guard cells that regulate gas exchange.
• Xylem: Vascular tissue responsible for the transport of water and minerals. Appears as thick-walled, tube-like cells.
• Phloem: Vascular tissue that transports food. Consists of thin-walled cells adjacent to the xylem.

Inference

This experiment highlights the presence and functions of different plant tissues:

• Epidermis: Protects the leaf and prevents water loss.
• Stomata: Facilitates gas exchange and transpiration.
• Xylem and Phloem: Part of the vascular system, transporting water, minerals, and food throughout the plant.

Video Reference