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Integrated Science
Name ________________________________
Comparing Plant and Animal Cells
Purpose:
To examine the similarities and differences between elodea and human
cheek cells.
Materials:
Student microscope
tooth pick
elodea (anachris)
2 slides
forceps
onion skin
2 cover slips
water and eye dropper
Methylene blue dye (optional)
Procedure:
1.
Prepare your own slide using two drops of water or methylene blue stain
(optional) in which a single leaf of the elodea plant is placed. Add a cover slip.
2.
Focus the plant leaf using LOW power (use correct procedures). Locate the
clearest area of the specimen. Observe and neatly sketch several cells as they appear
under low power.
3.
Focus this clear area on HIGH power (indicate magnification used), and draw a
neat, accurate sketch of two elodea cells. Include all details seen within each cell.
Low Power: _________ X
High Power: ________ X
4.
Label each structure inside the cells in your drawings, using the letter of the
descriptions listed below:
a. cell wall (outer wall)
b. cell membrane (thin liner--may be seen just inside cell wall)
c. nucleus (small oval, if using stain, will be stained darker )
d. cytoplasm (semiclear material that fills space inside cell)
e. chloroplasts (numerous ovals that may be circling within cytoplasm)
5.
Repeat steps 1-4 using an onion skin. Be sure to include appropriate labels
from step 4.
Low Power: ______ X
High Power: _______ X
6.
Wash your hands and use the flat edge of a toothpick to gently rub the inside of
your cheek. Make a fingerprint on a clean microscope slide. Place one drop of
methylene blue stain on top of your fingerprint. (NOTE: using the methylene blue stain
is optional, but worth trying!)
7.
Focus on LOW power and locate a single cheek cell that has not been folded.
Draw the cheek cell as it appears under low power.
8.
Focus this cell on high power and draw a neat, accurate sketch of it. Include all
details seen inside the cell. Be sure to use a cover slip on high power.
Low Power: _____X
9.
than
High Power: ______ X
Label the structures seen inside the cheek cells in your drawings,
a. cell membrane (outer membrane b. nucleus (small oval, stained darker
surrounding material)
Analysis:
1.
Compare the border of the plant cells to the animal (cheek) cell. What
differences can you note?
2.
What internal structures do human cheek cells have in common with elodea and
onion cells?
3.
What are some observed differences between the elodea cells and onion cells?
4.
What were the green structures found in the elodea cell but not found in the
onion cell?
5.
What do you think is the purpose of these bodies (Question 4)?
6.
What is the term used to describe the internal structures of a cell?
7.
Compare the structures of plant and animal cells. Give at least three examples
of differences you can see.
a.
b.
c.
8.
Plants are stiff and rigid. How does their cellular structure contribute to this
characteristic?
9.
What observations of the elodea cells suggest a central vacuole?