Structures of the Eukaryotic Cell
Lesson 3b
Name_____________________________ Period____________ Date___________________
Examining Cheek Cells
List the 3 parts of the Cell Theory.
a. ____________________________________________________________________
b. ____________________________________________________________________
c. ____________________________________________________________________
Write a short description of each of the following:
Cell Membrane
Cytoplasm
Nucleus
Organelle
Procedure:
1. Place a drop of methylene blue on a slide. Caution: methylene blue will stain clothes
and skin.
2. Gently scrape the inside of your cheek with the flat side of a toothpick. Scrape lightly.
3. Stir the end of the toothpick into the stain on the slide and throw the toothpick away.
4. Place a coverslip onto the slide and place the slide on the microscope.
5. Use the Low Power objective to focus. Cells should be visible, but they will be small and
look like nearly clear purplish blobs. If you are looking at something dark purple, it is
probably not a cell.
6. Once you think you have located a cell, switch to medium power and refocus.
(Remember, do NOT use the coarse adjustment knob at this point)
Sketch the cells in pencil. Label the nucleus, cytoplasm, and cell membrane.
Low power _____x
Medium power _____x
High power _____x
Human Cheek Cell
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Structures of the Eukaryotic Cell
Lesson 3b
Name_____________________________ Period____________ Date___________________
1. Why is methylene blue necessary?
2. What objective power on the microscope do you always start with?
3. The compound light microscope used in the lab is not powerful enough to view other
organelles in the cheek cell. What parts of the cell were visible?
4. As you move from a low power objective to a high power objective, what do you always
have to do first?
5. Is the cheek cell a eukaryote or prokaryote? How do you know?
6. What does the base word/term cyt or cyto mean?
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