MICROSCOPY
Exam questions on this section commonly require you to:
- Compare and contrast how the 2 microscopes work
- Comment on the limitations of the 2 microscopes
- Distinguish between the appearance of cells under the light microscope and electron microscope
- Describe an experiment in which you used light microscopy to view cells – both stained and unstained.
There are two types of microscope used to view cells:
- Light Microscope
- Electron Microscope
LIGHT MICROSCOPE
- Uses a beam of light to view specimen
- Uses glass lenses for magnification
- Average light microscope magnification – 400 times
- Eyepiece lens – magnifies image
- Coarse adjustment wheel – allows for rough focusing
- Objective lens – Magnifies Image
- Nosepiece – Revolves different objective lenses
- Stage/clip – revolves around different objective lenses
- Mirror/ light source – Supply light
- Diaphragm/ iris – Allows light intensities to illuminate the image
Typical Animal Cell Under Light Microscope
Typical Plant Cell Under Light Microscope

ELECTRON MICROSCOPE
- Uses beam of electrons to view specimen
- Uses magnets for magnification
- Cannot view living specimens – due to the staining and embedding of magnets
- Very high magnification- greater than 500,000 times
Animal Cell Under Electron Microscope
Plant Cell under Electron Microscope