Sec:_.__
Name:
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Experiment
Leeuwenhoek & Hooke's
Experiments (8. Science 10-7-1b)
!Purpose: T a repeat Leeuwenhoek and Hooke's
'early experiments with pond water and cork cells.
Materials: microscope slides
forceps
pond water
razor blade
coverslip
cork
Safety: Sharp Object Warning - handle
razor blade with care
Methods:
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Part A: Leeuwenhoek's Experiments with
pond water .
1. Leeuwenhoek examined many microorganisms thea had never been seen before
by humans. Today we will examine some pond water containing microorganisms.
Obtain a sample of pond water by using your pipet from the dissection kit. (Samples
taken carefully from bottom of pond water would give better results).
2. Carefully place a drop of this sample on the microscope slide.
3. Obtain a coverslip and prepare a wet mount of th!s
sample.
4. Observe wet mount under the microscope for
microorganisms. Observe under low power, and
when an microorganism is observed switch it to
a higher power (10x or even 43x) if possiblR
5. Draw two different organisms that you have observed in the wet mount preparation
Indicate magnification.
If none are present, try again by getting another sample.
6. When complete wash off the slide, and keep the coverslip for part B.
Part B:
Hooke's Experiments with cork cells.
1. Carefully shave a very thin section from a bottle cork with a razor blade.
2. Prepare a wet mount slide of the cork slice.
3. Examine the specimen under low power, studying it in different positions.
4. In the space provided draw a sketch of what you observe under low power. Record
magnification.
5. Then in the second space provided draw a sketch of what you observe under high
power. Record magnification.
See.:
Results: Part A:
Name:
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leeuwenhoek's Experiments with pond water.
x
x
low power observations
higher power observations
Part 8: Hooke's Experiments with cork cells.
x
low power observations
x
higher power observations
Conclusions:
1. How many different organisms did you observe in the pond water?
2. How would you describe the units that compose the cork?
3.
4.
5.
6.
Are these units that you observed in the cork of similar shape?
Are they of similar size?
Are they filled with any material?
If so (Question 5), explain what that content appears to be.
1. Are there spaces between the cells?
Discussion:
1. Are these cork cells alive?
2. What is the name of the individual units of cork seen under the microscope?
3. Discuss the role of following peoples's work in our understanding of cell theory?
Leeuwenhoek
Hooke
4. On what day of creation did God create the first cells here on Earth? Remember
both plants and animals are made up of cells. (Gen. 1)