T. Trimpe 2005
http://sciencespot.net/
Body Tube
Ocular lens
(Eyepiece)
Nosepiece
Objectives
Arm
Stage
Stage Clips
Coarse Adjustment
Diaphragm
Light
Fine Adjustment
Base
Always carry a microscope with one hand
holding the arm and one hand under the base.
What’s my power?
To calculate the power of magnification, multiply the power of the
ocular lens by the power of the objective.
What are the powers of
magnification for each of
the objectives we have on
our microscopes?
Comparing Powers of Magnification
We can see better details with higher the
powers of magnification, but we cannot see
as much of the image.
Which of these images
would be viewed at a
higher power of
magnification?
LET’S GIVE IT A TRY ...
1 – Turn on the microscope and then rotate the nosepiece to click the
red-banded objective into place.
2 – Place a slide on the stage and secure it using the stage clips. Use
the coarse adjustment knob (large knob) to get it the image into view
and then use the fine adjustment knob (small knob) to make it clearer.
3 – Once you have the image in view, rotate the nosepiece to view it
under different powers. Draw what you see on your worksheet!
Be careful with the largest objective! Sometimes there is
not enough room and you will not be able to use it!
4 – When you are done, turn off the microscope and put up the
slides you used.
How to make a wet-mount slide …
1 – Get a clean slide and coverslip from your teacher.
2 – Place ONE drop of water in the middle of the slide. Don’t use
too much or the water will run off the edge and make a mess!
3 – Place the edge of the cover slip on one side of the water drop.
4 - Slowly lower the cover slip on top of the drop.
Cover
Slip
Lower slowly
5 – Place the slide on the stage and view it first with the red-banded
objective. Once you see the image, you can rotate the nosepiece to
view the slide with the different objectives.
You do not need to use the stage clips
when viewing wet-mount slides!
Onion Cell
Under High
Power (400x)stained with
iodine. Why
stain the cells?
1.
Nucleus
Cell Wall
2.
Cytoplasm
3.
Elodea Leaf
Cells Under
High Power
(400x)
Cell Wall 1.
Chloroplast 2.
Cytoplasm 3.
Tomato
Skin vs Pulp
Potato Cells
With Amyloplasts
Cheek Cell
Red Onion Cell
Under High
Power (400x)in tap water
(100% water).
Cell Wall
1.
Cytoplasm
2.
3.
Cell
Membrane
around the
cytoplasm
after the
onion cell is
placed in salt
water.
Cell Wall
4.
Cytoplasm
5.
Isotonic Hypotonic and Hypertonic Solutions.mov - YouTube
EUKARYOTIC VS. PROKARYOTIC CELLS
Eukaryotic Cells
• Large
• Have chromosomes
• Have membranebound organelles
• Nucleus
• Mitochondria
• Centrioles
• (theory of
endosymbiosis)
Prokaryotic Cells
• Small
• No
chromosomes,
only small circle
of DNA (plasmid)
• No membranebound
organelles.
Eukaryotic Cells are Larger than Prokaryotic cells
PROTISTA
•
•
•
•
The most ancient eukaryotic kingdom
Eukaryotic
heterotrophic, autotrophic, or both
Perhaps they are best defined as
eukaryotes that are NOT fungi, animals, or
plants.
(Ex- Amoeba, Paramecium, Euglena)
PROTISTS
AMOEBA
Amoeba moving
Amoeba feeding