Download The Onion Cell Lab

Miss Jones
Science 8
Scientific Drawing Lab: Plant and Animal Cells
Background: Prepared cells are a great way to observe cell structure. Today, we will be looking
at prepared plant and animal cells. These prepared slides are made take a very thin sample of
the organism and using a dye to make the cell structure more obvious. In these slides, we should
be able to observe a cell wall and large vacuole (in plant cell slides), nuclei and cell
membrane. If we are lucky, we might be able to see a nucleolus inside the nuclei as well!
Purpose: To study the structure of the onion cell and animal cheek cell using prepared slides.
Materials: Microscopes, prepared slides and these lab notes
Remember, microscopes are expensive and breakable! For this reason, we follow the following
steps:
Before Starting:
1. Use both hands to pick up the microscope: One on the neck, one supporting beneath the
base
2. Plug in cord
3. Open the diaphragm all the way to let as much light in as possible
4. Ensure it is set to low power
5. Move stage all the way down using the coarse adjustor knob
Starting:
6. Place slide on the stage
7. Use the coarse adjustment knob to find and focus the object (on low power and make
sure the object is centered)
8. Switch to medium. Use the fine adjustment knob to focus the object
9. Switch to high. Use the fine adjustment knob to focus the object
10. Remember, never use the coarse adjustment knob when on medium or high power!
Clean up:
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Remove the slide
Move the stage all the way down
Switch to low power
Turn off light source
Unplug and wrap cord
Return to microscope cart
For this lab, you will be making scientific drawings. An example of this will be done in class, but
follow the example below if you forget.
Procedure:
1. Listen to the instructions to find out whether you start with the animal cell slides or plant
cell slides.
2. Have one partner get the microscope, while the other gets the slide.
3. Follow the instructions above on how to use a microscope to focus on the object.
4. Draw the object in one of the large circles following the rules for biological drawings
5. Label only what you can see
6. Switch to the other cell type when time is called and repeat these steps.
7. Answer the questions below.
8. If finished, you may get additional prepared slides and do more drawings or look at the
real onion cell that Miss Jones has at the front.
Drawing Lab Check list:
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I have used a pencil.
I have drawn a plant cell in one circle.
I have drawn an animal cell in a different circle.
I have included the total magnification that was used at the bottom of each drawing
Both drawings are large (take up the entire circle)
For both drawings I have included an accurate title
For both drawings I have included at least two qualitative observations written at the
bottom of the diagram
For both drawings I have labeled everything I can see. The labels are to the RIGHT
hand-side and the lines are drawn using a RULER. The lines do not cross.
I have NOT labeled anything that I couldn’t actually see
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Questions:
1. What are some of the benefits of using prepared slides instead of creating slides in the
lab?
2. What is the function of the nucleus?
3. Where is the nucleolus found and what does it produce?
4. Describe what ribosomes do in the cell.
5. What are the main differences between plant and animal cells.
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