1. Microscope
Biology 101
Ms. Miller

2. Types of Microscopes Light microscope Stereoscope
Compound lenses to magnify objects.
Lenses refract light to make object appear closer.
40x, 100x, 400x
Stereoscope
Allows binocular viewing of larger specimens.

3. Types of Microscopes Scanning Electron Microscope
Use electrons to magnify objects instead of light waves.
Can magnify up to two million times.
Transmission Electron Microscope
Uses electrons as well.
Electrons are passed through very thin specimens.

4. Lenses Three magnification lenses Scanning Low power High power
4x magnification
Low power
10x magnification
High power
40x magnification

5. Lenses Ocular lens In addition to the magnification lenses.
10x magnification

6. Magnification
To find the total magnification multiple the magnification of the lens by the magnification of the ocular lens.
Magnification
Ocular Lens
Total Magnification
Scanning 4x
10x
40x
Low Power
100x
High Power
400x

7. Focusing Always start with the scanning objective.
Coarse knob to focus.
Once you’ve focused on scanning, switch to low power.
Coarse knob to refocus.
Switch to high power.
Fine knob to refocus.

8. Focusing Can’t see the specimen? See a line?
Is it too light or too dark?
Adjust the diaphragm.
See a line?
It is a pointer
Useful for pointing things out to partner or teacher.
Try twisting the eyepiece

9. Drawing Specimens Use pencil.
Drawing should be large enough to see detail.
Label items in drawing.
Write what magnification you are viewing the object at.
Label the object.

10. Drawing Specimens
Cell
Membrane
Ameba (400x)
Nucleus

11. Clean Up & Storage Make sure the scanning lens is in place.
Wrap cords around the base.
Cover microscope.
Wash and dry slides before placing them back in slide box.
Cover slips are to be thrown away.