The
Mi croscope
COMPOUND
MICROSCOPE
• Compound = 2 lenses
– Ocular Lens (10x)
– Objective Lens (4x,10x,40x)
Using the Microscope!!
Rules
1. Always use lowest power to
scan the slide for the specimen.
Scanning
Rules
2. Never use
coarse
adjustment with
high power
objective!
HOW TO USE
1.
Set the microscope to the lowest power objective.
2.
coarse adjustment
Lower the stage all the way using the ____________________.
3.
Place the ____________
slide on the ________________.
stage
4.
Use the ________
coarseadjustment to bring the stage all the way up.
5.
Then focus on the object using the coarse adjustment.
6.
Then use the ____________
fine adjustment to focus better.
7.
Find what you are looking for and place it in the center of the field of
view.
8.
coarse adjustment.
stage by using the __________
Lower the ____________
9.
Switch to the ___________
high power objective.
fine adjustment
10. Then focus, using only the _______________________.
Field of View(vision)
• The area that can be seen
through the microscope.
100x
400x
• Is the field of view larger or
smaller under high power?
FOV
• The lower the magnification, the Larger the
Field of view.
• The higher the magnification, the smaller the
field of view.
• There is less light.
• You need to adjust the
diaphragm.
Field of View
• Under high power: The FOV is
SMALLER and DARKER!
100x
Low Power
400x
High Power
Depth of Field: the
level you are
focused on
A Paramecium moves to
different levels of depth
when it swims.
Depth of field
• Use the fine adjustment knob to get to the
depth that you want to see.
Finding Total Magnification
Ocular Lens
X
Objective Lens
LP: 10x X 15x =150x
HP: ___X___=____
What is the lowest possible magnification that
can be obtained using the microscope
shown?
1.
2.
3.
4.
20x
200x
10x
100x
Microscope Lab
Examine the
functions and
magnification
of your
microscope.
How to make a wet mount
• 1. Place specimen on a glass slide.
• 2. add a drop of water
• 3.Lower glass cover slip on an angle to avoid air
bubbles.
• 4. examine under low power.
• Note: if stain is to be used, place drop of stain
on one side of slide and pull it through using a
paper towel.
How to Make a Wet Mount
https://www.youtube.com/watch?v=msPQPwOa5J8
To avoid air
bubbles under
your slide,
touch the
coverslip to
the drop then
lower it slowly,
squeezing the
drop.
The diagram represents a hydra as
viewed with a compound light
microscope. If the hydra moves to the
right of the slide preparation, which
diagram below best represents what will
be viewed through the microscope?
The diagram to the left represents
the letter "h" as seen in the low
power field of view of a compound
light microscope. Which diagram
below best represents the field of
view if the slide is not moved and the
objective is switched to high power?