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Cell Discovery Lab

A journey back in time… Around the same time Robert Hooke looked at cork and coined the term “cells,” a man named Anton Van Leeuwenhoek began to look at pond water underneath a simple microscope he built. With the help of his microscope, Leeuwenhoek discovered small living things he called “animalcules.” Today, these animalcules are now called protists. Your challenge for this lab is to go back to the 17th century and reenact Leeuwenhoek’s discovery.

Materials: Compound Light Microscope; Slide; Cover Slip; Pond Water or “Reef Water”; Eyedropper

Procedure:

1. Using the eyedropper, place a single drop of pond water or reef water on a clean, dry slide.
2. Place a cover slip over the drop of water. Lower the cover slip at an angle so air does not get trapped underneath.
3. Observe the “animalcules.” Carefully observe the pond water under all three of the objectives (4X, 10X, and 40X).
4. Draw the “animalcules” you see under each magnification and record the total magnification you are using.

Observations:

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Analysis:

1. What were your first thoughts the first time you saw the “animalcules” (aka protists)?

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2. If you were the first one to discover these organisms, what would you have called them?

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3. Describe the most interesting thing you observed today under the microscope.

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