1. HOW TO USE THE MICROSCOPE

2. Unlock a whole new view of the world under the microscope!

3. The Compound Light Microscope
Has two magnifying lenses
* Ocular (eye lens)
* Objective lenses (high, medium, low)
Uses light for viewing
Most commonly used microscope

4. REVIEW of the Basic Parts of the Microscope

5. What does each part do?

6. Magnification
The ocular lens (eyepiece) has magnification written on it.
Each microscope has 3 or 4 objective lens with magnification written on it.
Ocular lens x Objective lens = Total Power Power Magnification
Low ___ x ___ = ___ magnification
Med. ___ x ___ = ___
High ___ x ___ = ___

7. Let’s check your memory…

8. Carrying a microscope Use both hands One hand under the base
One hand holding the arm
Carry the microscope close to your body.

9. Resolving Power = ability to see details clearly
Resolving power is reduced as you go to higher powers of magnification
Fabric 40 x x

10. Field of View Lighted circle when looking through the ocular
On higher magnification not everything in field will be in sharp focus this is how you know the specimen has depth, layers

11. Orientation of Specimens
Letter e on a slide put under the microscope.
As seen under the microscope
What does this tell you about what the lens system does to a specimen?

12. The Art of Focusing Step 1- Obtain a slide and place it on
the stage over center of
opening.
Step 2- Rotate the nosepiece so that low
objective is in line with the body
tube.

13. Step 3- Raise the body tube using
coarse adjustment knob until
lens is 2 cm above stage.
Step 4- To begin to focus on low power,
use the coarse adjustment
knob. When specimen comes
into view, then use the fine
adjustment to bring specimen into
sharp focus.

14. Step 5- Adjust the diaphragm (amount of
light) to get the most detailed view.
Step 6- Increase to a higher magnification
by rotating the nosepiece until
objective clicks into place.
Step 7- Use only the fine adjustment knob
to focus images on medium and
high power.

15. When finished viewing a slide..
If viewing another slide, start on low power and repeat the focusing process.
If finished for the day, remove slide from stage and return to origin.
Clean any slides made by you.
Rotate eyepiece to lowest objective .
Turn off light.

16. Making a Wet Mount Slide
Step 1- Obtain a clean slide and coverslip.
Step 2- Place specimen in the middle of the slide. .

17. Step 3- Place a drop of water on the specimen.
Step 4- Slowly lower the cover slip at a 45 degree angle until it touches slide. Gently tap out any air bubbles if present.

18. Step 5- Remove excess water at edge of coverslip with a paper towel
Step 5- Remove excess water at edge of coverslip with a paper towel. (If specimen dries out while viewing add a drop of water at edge of cover slip.)

19. Making a Stained Slide
Follow the same procedures as for making a Wet Mount Slide, except use the stain specified in directions.

20. Stains allow you to see more detail and structures, depending on the stain used.

21. Teacher Check- Slide Preparation
Your slide under the microscope will be checked using the following criteria:
____ Started with clean materials
____ Complete water (or stain) coverage, edge to edge
____ No visible air bubbles.
____Specimen is centered under slide.
____ Specimen is focused and in view (under magnification
directed in lab directions.)

22. Guidelines for Biological Drawings
Drawing Materials: use a pencil NOT a pen (so as to allow for erasing and shading), used colored pencils if image is seen in color
Positioning: Field of view= circle, position drawing as you see in
your circular field of view

23. Size- Draw to scale (what you see in the field of view is drawn similar size on your paper field of view- circle)
Accuracy: Carefully observe what you “see” under the microscope
Draw what you see! Pay attention to details like- texture, size, color, shapes

24. Labeling Slide Diagram
Labeling : Label all specimen parts that
are known to you and/or stated in
the directions to be labeled
EX: label cell wall, membrane, nucleus
Title: title of slide, or what is being
viewed
Magnification: state the power that is
being viewed and diagrammed
Type: prepared slide, stained slide, or
wet mount

25. Diagram Teacher Check
You will be assessed on your diagram skills using the
following criteria. DO NOT remove your slide from
the stage, since it is needed to compare to your
diagram.
___ Accuracy – Diagram looks similar to what was
observed
___Detailed-- Details such as color, texture, shape, etc.
are included in diagram
___ Size-Diagram is of appropriate size to see details,
drawn to scale
___ Labeling-All parts of the diagram are labeled as
instructured in lab directions.
___ Slide Labeled-Title, Magnification, Type, is included

26. REVIEW- Homework Assignment
Use your textbook, Appendix D Use of the Microscope and Slide Preparation Procedures (starting on page 1070) to assist you.
Microscope Structures, Functions and Magnification (page 1 in new packet)
Steps of Using a Microscope, Steps to Making a Wet Mount Slide (page 2 in new packet)