Activity: Examining Plant Cells

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Activity: Examining Plant Cells
Goals:
1. To observe the major structures found in a typical plant
cell.
2. To compare the structures of an animal cell with those of
the plant cell.
Background Information: Three structures make plant cells different from animal cells.
These structures are the cell wall, a very large vacuole and chloroplasts. You will
notice these structures immediately when you look at plant cells under the microscope.
(The most visible structures of an animal cell are the nucleus, cytoplasm, and cell
membrane.)
Cell walls help a plant maintain its shape and give the plant support. If the wind blows,
the plant doesn’t droop over, it’s able to bounce back and stand up straight. The cell
walls also provide elasticity. No matter what happens to the plant cell, the cell
maintains its shape. Sometimes the cell inside the wall will shrink, or swell, but the cell
wall keeps all of the parts of the cell in a specific area.
In plant cells, the vacuoles are much larger than in animal cells. Sometimes a plant
vacuole can take up more than half of the cell’s volume. The vacuole acts like a storage
container and holds large amounts of water, food, or wastes. The large vacuoles and
cell wall work together to maintain the box-like shape of the plant cell.
There are many chloroplasts in a plant cell. Chloroplasts take energy from the sun and
create food in the form of a simple sugar called glucose. (This text was summarized
from the Biology4Kids website.)
Materials: blank slide, cover slip, scissors, eyedropper, water, Elodea leaf tip, tweezers,
paper towels
Procedure:
1. What I Know: Write two sentences about what you already know about plant
cells.
2. Create a wet mount using the Elodea leaf tip. Carefully cut the “growing end’
from the tip of an Elodea leaf. (This piece should be about 5 mm in size.)
3. Place the Elodea leaf tip onto a drop of water that has been placed on a blank
slide. Cover the specimen with a cover slip.
4. Beginning at 40X observe the plant cells. Move the slide around until you find an
area of plant cells where it is easy to see individual cells.
5. Continue your observations at 100X and 400X.
6. What I Observed:
 Illustrate your best view of the plant cells at either magnification (100X or
400X).
 Label the cell wall and a chloroplast. Try to find and label the cytoplasm, a
vacuole, and cell membrane. These last three structures might be more
difficult to find.
 Write a caption for your drawing that describes your observation in detail.
a. Illustration and Labels:
b. Caption
______ X
7. What I Learned: Summarize what you learned about plant cells from doing this
activity. Be specific. Look at the goals for the activity to help you structure your
response.
8. What I Wonder: Pose a “why” or “how” question about what you would still
would like to know about plant cells or wonder about plant cells.
9. Questions: Answer the following questions in complete sentences. Use your
textbook as a resource.
a. Compare and contrast the functions of a cell wall in a plant cell and
functions of a cell membrane in an animal cell.
b. How is a vacuole of a plant cell different from that of an animal cell?
c. Why is a chloroplast important to the function of a plant?
Name ___________________________________
Date _______
Title of Activity: _____________________________________________
1. What I Know:
2. What I Did:
3. What I Observed:
a. Illustration and Labels:
______ X
b. Caption:
4. What I Learned:
5. What I Wonder:
6. Questions:
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