Name___________________
LAB # 7: COMPARISON OF PROKARYOTIC (BACTERIA) CELLS
AND EUKARYOTIC (PROTIST) CELLS
INTRODUCTION
In this lab, students will use microscopes to compare and contrast the structure of
prokaryotic cells (bacteria) with those found in single-celled eukaryotic cells (Protists).
OBJECTIVES:
By the end of this exercise, you should be able to...
explain how the cell is the basic unit for all living things.
relate characteristics of living things to cell structure.
diagram prepared slides of prokaryotic cells (bacteria) and label the cell wall, cell membrane, and
cytoplasm. Identify the shape of the species of bacteria.
measure the length and width of bacteria cells in micrometers.
diagram eukaryotic cells (Protists) and label the cell membrane, cytoplasm, nucleus, and any other
organelles that are visible.
measure the diameter of Protist cells in micrometers.
compare and contrast Prokaryotic (bacteria) cells with eukaryotic (Protist) cells.
HYPOTHESIS:
If a cell is identified as a Prokaryote, we will be able to identify the ___________.
(List structures you expect to see)
If a cell is identified as a Eukaryote, we will be able to identify the ___________.
(List structures you expect to see)
PROCEDURE PART A: EUKARYOTIC CELLS (PROTISTS)
1. Acquire a prepared slide of Single-Celled Eukaryotes (Protists).
2. Label the species of Protist in your lab notebook.
3. Focus the slide under the low power (40x) objective and move the slide to find good
examples of these cells. Diagram the cells in your lab notebook. Label the cell
membrane, cytoplasm, nucleus, and any other organelles that are visible.
4. Focus under (100X) power and diagram.
5. Focus under (400X) power and diagram.
6. Estimate the size (length, width, diameter) of a single cell. You may choose to
estimate the size under any power objective. (Remember this from Measuring with
a Microscope Lab?)
PROCEDURE PART B: PROKARYOTIC CELLS (BACTERIA)
1. Acquire a prepared slide from the box labeled "Single Celled Prokaryotes
(Bacteria)".
2. Label the species of Bacteria in your lab notebook.
3. Focus the slide under the low power objective (40x) and move the slide to find good
examples of these cells. Diagram the cells in your lab notebook.
4. Focus under 100x and diagram.
5. Focus under 400x and diagram. Label the cell membrane, (cell wall), and
cytoplasm.
6. Estimate the size (length, width, diameter) of a single cell. You may choose to
estimate the size under any power objective.
Analysis and Conclusion:
Comparing Prokaryotic and Eukaryotic Cells
Answer the following questions and statements using complete sentences in your lab
notebook.
1. Explain the importance of the presence of the nucleus in eukaryotic cells and tell how
lacking this structure impacts the survival of prokaryotic cells.
2. What structures do both prokaryotic and eukaryotic cells have in common?
3. Explain the significance and reasons why these structures are common to both cell
types.
4. What structures (organelles) do eukaryotic cells have that prokaryotic cells do not?
What effect does this have on the survival of Eukaryotic cells?
5. Compare the size and shape of both eukaryotic cells and prokaryotic cells.
6. Give examples of single celled organisms that are prokaryotic. Give the Species
names of at least 5 representatives that you come in contact with on a daily basis.
7. Give 5 examples of single celled organisms that are eukaryotic and identify where you
might find each of these things.
Diagrams
In the Column 1, diagram a single bacterium (prokaryotic cell). Be sure to tell the total
magnification, identify the cell, label the cell wall and cytoplasm, and indicate the size of
the cell.
In Column 2, diagram a single celled Protist (eukaryotic cell). Be sure to tell the total
magnification, identify the cell, label the cell membrane, cytoplasm, nucleus, and other
organelles, and indicate the size of the cell.
1. Bacterium (Prokaryotic cell)
2. Protist (Eukaryotic cell)
Magnification:
Magnification:
Object:
Object: