Name___________________________________________Pd_________Date________
Mr. Orend
Microscope Procedures

DO start on low power and work up towards a high power. Return to low power if you ‘lose’ your sample.

DO adjust light levels (more light with higher powers)
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DO use stains to color cells if required.

DO NOT use the coarse focus when on the high power.

DO put the scope away on low power.
*****SAFETY PRECAUTIONS*****:\

A CUTTING HAZARD is present when using the razor blades or scalpels. DO
NOT cut towards your hand. ALWAYS cut with the blade facing away from oneself. Ask the teacher if you need assistance.

Students that are ALLERGIC to iodine SHOULD NOT HANDLE these samples.
Let your partner stain, handle, and clean these slides.

Toothpicks used to harvest cheek cells present a BIOHAZARD. These toothpicks should be THROWN AWAY immediately after use to prevent the spread of germs and viruses.

Use aprons and goggles during lab. Only when looking at samples under the microscope should eye protection be removed.

Be careful not to get any stain on hands or clothing. IT WILL NOT come out of clothes, but will come off stained hands eventually.
Be sure to follow all laboratory procedures and safety precautions carefully. Ask the teacher if you need any assistance.
TASK 1: Letter “e” slide preparation
A. Cut out a single letter “e” from the sheet of paper with scissors.
B. Place the letter in the center of the blank slide RIGHT-SIDE UP.
C. Add one drop of water to the letter.
D. Cover the sample with a cover slip

TASK 1: Wet mount of the letter “e”
1. Turn on the microscope and p lace the slide on the stage; making sure the “e” is facing the normal reading position.
2.
Using the coarse focus and low per the “e” can be seen clearly.
Draw what you see in the first circle below.
3. Practice changing the objective lenses and focusing each time.
4.
Draw the “e” at low and medium power levels. Label the pictures on the next page.
MAGNIFICATION
SAMPLE
: 100X
: letter “e”
MAGNIFICATION : 400X
SAMPLE
: letter “e”
5. Compare the position of the “e” between how it is on the stage and how it appears through the scope. Use words like upside down, right side up, forwards, backwards, etc.
6. Looking through the eyepiece, move the slide to the upper right area of the stage.
What direction does the image move? (be specific!!!!) Describe why you think this might be happening.

TASK 2: Cheek cells slide preparation
A. Place one drop of water on the center of a blank slide.
B. Use the toothpick to swab the inside if your cheek for 5-10 seconds.
C. Swirl the end of the toothpick used to swab cheek in drop of water for 5-10 seconds.
D. THROW THE TOOTHPICK AWAY!
E. Add one drop of methylene blue stain.
F. Cover the sample with a cover slip.
TASK 3: Cheek Cells
7.
View the cells under all powers. Draw your observations below for medium and high powers.
8.
Label the cell membrane, nucleus, cytoplasm, and one entire cheek cell on both medium and high powers.
MAGNIFICATION : 100X
SAMPLE : Cheek cells
STAIN: Methylene blue
MAGNIFICATION : 400X
SAMPLE : Cheek cells
STAIN: Methylene Blue

TASK 3: Onion cells slide preparation
A. Cut off a small piece of onion. BE CAREFUL USING BLADES!
B. Carefully break the piece of onion cell, and peel away a thin strip of onion skin. This skin should be as thin as possible.
C. Place the onion skin on the center of the slide.
D. Add one drop of water.
E. Add one drop of iodine. HAVE YOUR PARTNER DO THIS IF YOU’RE
ALLERGIC!!! DO NOT TOUCH THE SLIDE IF YOU ARE ALLERGIC!!!
F. Cover the sample with a cover slip.
TASK 4: Wet mount of onion cells.
9.
View the cells under all powers. Draw your observations below for medium and high powers.
10.
Label the cell wall, nucleus, cytoplasm, and one entire onion cell on both medium and high powers.
MAGNIFICATION : 400X
SAMPLE : Onion cells
STAIN: Iodine
MAGNIFICATION : 100X
SAMPLE : Onion cells
STAIN: Iodine

TASK 4: Choose any prepared slide of your choice from the box of slides and sketch it below.
MAGNIFICATION : 100X
SAMPLE : _____________ ____
STAIN: Prepared
MAGNIFICATION
SAMPLE
STAIN: Prepared
: 400X
: ________________
TASK 5: Choose any prepared slide of your choice from the box of slides and sketch it below.
MAGNIFICATION : 100X
SAMPLE : _____________
STAIN: Prepared
MAGNIFICATION : 400X
SAMPLE : ________________
STAIN: Prepared

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TASK 6: Choose any specimen of your choice and use the appropriate stains for the sample.
DO NOT USE BODILY FLUIDS. AS THESE COULD BE BIOHAZARDS!!!
Iodine for plant samples. Methylene blue for animal cells.
MAGNIFICATION : 100X
SAMPLE : _____________
STAIN: _______________
MAGNIFICATION : 400X
SAMPLE : ________________
STAIN: __________________
Make 3 observations below about your chosen specimen.

ANALYSIS
Questions:
7.
Why are there no chloroplasts in an onion cell even though they are plant cells?
8.
Decide whether the cells you viewed were prokaryotic or eukaryotic. What data support your answer? Explain.
9.
Notice the difference in shape and arrangement between the plant cells (onion and elodea) and animal cells (your cheek cells). Describe the differences in shape and arrangement. What structures do plant cells have that animal cells lack? Do you think there is any connection with these structures and the shape/arrangement differences seen between animal and plant cells?