Comparing Plant and Animal Cells

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Comparing Plant, Animal, and Bacteria
Cells
Problem: How are plant, animal, and bateria cells alike? How are they different?
Procedure: In this lab, you will view cells from your cheek (animal cells), cells from an
onion, which is a plant, and bacteria cells found in yogurt. Careful observation should
reveal similarities and differences between the cells.
Cheek Cells
Gently scrape a toothpick over the inside of your cheek and swirl it in a drop of
methylene blue to stain the cells (otherwise they will be clear and difficult to see). You
are looking for light colored blobs with dark spots in them. Perfect circles with black
outlines are airbubbles. Don't sketch those. Sketch the cheek cells under low and high
power. Make sure you are drawing your cells to SCALE - that is, the size of your
drawing should reflect the size that you view them in the microscope.
Low Power
High Power
1. Identify the NUCLEUS on your
drawing.
2. Identify the CELL MEMBRANE
on your drawing.
3. Identify the CYTOPLASM (area)
on your drawing.
Elodea Cells
Cut a small peice of elodea leaf and prepare a wet mount. When you are looking for cells,
you should find a lot more than you found with the cheek cells, and it will resemble a
green brick wall. Sketch your cells under low and high power, also paying attention to
scale. The nucleus of these cells will not be visible but you should see many chloroplasts
within each cell. Plant cells also have a rigid cell wall, outside the cell membrane. The
Cell wall should also be visible.
Low Power
High Power
1. Identify the
CHLOROPLASTS on your
drawing.
2. Identify the CELL WALL
on your drawing.
3. Identify the
CYTOPLASM (area) on
your drawing.
4. Identify the CENTRAL
VACUOLE on your
drawing.
Analysis - Venn Diagram
Create a Venn Diagram of plant and animal cells. Remember, things that they have in
common go into the overlapping area, things that are different go in the non-overlapping
area.
Bacteria Cells
Prepare a wet-mount slide by using a toothpick to mix a tiny dab of yogurt with a drop of
water and then adding a coverslip. The mixture should have clear areas; it should not be
entirely opaque. Observe under progressively higher magnification to locate the bacteria,
which will be floating in between the areas of coagulated protein and other milk solids.
Sketch your cells under low and high power, also paying attention to scale.
Low Power
High Power
Analysis - Venn Diagram
Create a Venn Diagram of eukaryotic and prokaryotic cells. Remember, things that they
have in common go into the overlapping area, things that are different go in the nonoverlapping area.
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