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“Cell”abration Lab
What will living cells (and one dead one) look like under the light microscope? How much detail will we see? In what ways will
different cells look similar? Different?
***Drawings MUST be made in Petri dish circle and include title, labels, captions and total magnification***
Question(s)
What organelles or cell structures can be seen with a light compound microscope?
Hypothesis: You don’t need an “If, then” statement because there is no manipulated or responding variable.
Materials
Microscope, slides, coverslips
flat toothpicks (clean)
live or dead cellular material
cell stains (iodine and methylene blue)
water bottle
Procedure
Make wet mounts of the available cell types. Work at your own pace and you may go in any order. You will need to share
light microscopes with your lab partner so work together.
Remember:

When doing a wet mount, only use ONE DROP OF WATER.

Focus on your sample on LOW power; go up to MEDIUM or HIGH to fine your focus.

ADJUST FINE FOCUS ONLY AFTER USING 4x.

Draw what you SEE. LABEL the structures you recognize. Remember to figure your total
magnification multiply the eyepiece (10x) by the ocular power you are looking through (4x, 10x or 40x)
Required specimens:
Elodea:
Tear off one young leaf from the plant and make a wet mount of it. Do NOT stain; enjoy its natural color! After
locating a “good” area, use FINE FOCUS to bring just one layer of Elodea leaf cells into view. What are the green
organelles floating around?
Cheek:
With a flat, clean toothpick, scrape gently the inside of your mouth. You’ll pick up many cheek lining cells
(epithelial tissue), though you won’t see them yet! Smear the toothpick on a slide to spread out the cells. Stain
with methylene blue and add a cover slip.
Onion:
Remove one of the fleshy ‘scale’ leaves from an onion. Snap the piece of onion backward to produce a ragged piece
of epidermis. It is very thin; peel it off and make a wet mount. Stain with iodine.
Yogurt:
Put VERY small amount of yogurt and a drop of water on a slide and make a wet mount. Do NOT add stain.
FOCUS on low and medium, but use HIGH POWER to draw these tiny cells. They will be rod shaped and may be
difficult to see.
Fujii
Cell Lab
You should have a total 7 pictures in your data section. Please only 2 pictures per page.
Data

Sketch your field of view for each cell sample in a circle (use a petri dish lid). Label parts of one cell in your field of
view.

Color your observations.

Include a title stating what cell you are examining.

Include a caption and the power under which you examined your specimen. (caption should include what cell type you are
looking at, organelles present, and what stain, if any, was used)

Make the following observations for each cell to put in your caption:
o What kind of cell is it (pro. or eu., and plant or animal)?
o What organelles are present?
o What is the shape of the cell?
o Did you use a dye and any interesting observations?
o Total Magnification
Conclusion There is no conclusion statement for this lab, because there was no hypothesis.
Post-Lab Questions
Base all your answers for the following questions on your observations, NOT what you already know about the cell.
1. Are your obervations what you think they would be before you began the experiment?
2.
How did the size of prokaryotes differ from eukaryotes in your observations? Refer to your observations.
3.
How did the presence of certain organelles differ between plant and animal cells? Refer to your observations.
4.
What organelles or cell structures were present in ALL cells you observed? Explain why you saw this/these parts
compared and not others.
5.
When observing the elodea leaf, you saw the green circular object moving. What are the green objects? What do
you think caused them to move?
6.
We discussed many different organelles, yet you don’t see them. Why? Does that mean they don’t exist? Explain.
7.
Why did some of the wet mounts you made need dyes?
8.
Some of the cells you saw looked like they contained two nuclei. Explain this phenomenon.
Fujii
Cell Lab