This deep dive covers Required Practical: Using a Light Microscope within Microscopy for GCSE Biology. Light and electron microscopes, magnification and resolution calculations, specimen preparation, staining techniques, and practical microscopy skills It is section 7 of 19 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 7 of 19
Practice
18 questions
Recall
20 flashcards
🧪 Required Practical: Using a Light Microscope
Aim:
To use a light microscope to observe, draw and label a selection of plant and animal cells
Equipment:
- Light microscope
- Microscope slides and coverslips
- Specimens: onion epidermis, cheek cells
- Stains: iodine solution, methylene blue
- Dropping pipette
- Filter paper or paper towel
- Mounted needle
- Ruler
Method:
- Set up microscope: Start with lowest magnification (×4 or ×10 objective)
- Prepare specimen: Place thin section on slide
- Add stain: Add 1-2 drops of appropriate stain
- Add coverslip: Lower at 45° angle to avoid air bubbles
- Place on stage: Secure with clips
- Focus on low power: Use coarse focus knob
- Center specimen: Move slide to find interesting area
- Switch to high power: Rotate to higher magnification
- Fine focus only: Use fine focus knob for sharp image
- Observe and record: Draw what you see with labels
⚠️ Safety Considerations:
- Handle slides and coverslips carefully - sharp edges
- Never force focus knobs
- Clean lenses with lens paper only
- Wash hands after handling stains