This diagram covers Size Calculations within Microscopy for GCSE Biology. Light and electron microscopes, magnification and resolution calculations, specimen preparation, staining techniques, and practical microscopy skills It is section 6 of 20 in this topic. Focus on the labels, the relationships between parts, and the explanation that turns the diagram into an exam-ready answer.
Topic position
Section 6 of 20
Practice
26 questions
Recall
20 flashcards
📏 Size Calculations
The Triangle Method:
- I = Image size (what you measure)
- A = Actual size (real size)
- M = Magnification
Key Formulas:
Magnification = Image Size ÷ Actual Size
Actual Size = Image Size ÷ Magnification
Image Size = Actual Size × Magnification
Worked Example:
Question: A cell appears 30mm long under ×400 magnification. What is its actual size?
Solution:
- Image size = 30 mm
- Magnification = ×400
- Actual size = Image size ÷ Magnification
- Actual size = 30 mm ÷ 400 = 0.075 mm
- Convert to micrometers: 0.075 mm × 1000 = 75 μm
Keep building this topic
Read this section alongside the surrounding pages in Microscopy. That gives you the full topic sequence instead of a single isolated revision point.
Practice Questions for Microscopy
What is magnification?
Explain why specimens are stained before viewing under a light microscope.
Quick Recall Flashcards
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