Required Practical 1: Using a Light Microscope

Equipment Needed:

• Light microscope
• Microscope slides and coverslips
• Prepared specimens (onion cells, cheek cells)
• Iodine solution (stain)
• Dropping pipette
• Filter paper

Method:

1. Set up the microscope: Start with lowest magnification objective lens
2. Prepare the specimen: Place thin section on slide, add stain if needed
3. Add coverslip: Lower slowly to avoid air bubbles
4. Focus on low power: Use coarse focus knob first
5. Switch to higher magnification: Use fine focus knob only
6. Observe and draw: Label the structures you can see

Key Observations:

• Onion cells: Cell wall, nucleus, cytoplasm
• Cheek cells: Cell membrane, nucleus, cytoplasm
• Plant vs Animal: Compare the shapes and structures