Protista and Friends
By Taylor Courtney
Lab Procedure
Protista
Discovering protista
On December 25, 1702, Leeuwenhoek wrote a letter about finding a ciliate, which was the protist Vorticella.
"In structure these little animals were fashioned like a bell, and at the round opening they made such a stir, that the particles in the water thereabout were set in motion thereby. . ."
- Leeuwenhoek
Leeuwenhoek's discoveries just increased from there. Several other scientists, including Robert Hooke, also made important discoveries about protists.
Protista evolution
This new discovery has led to more questions about protist evolution, but it also opened new doors about what protists may have gone through in history.
Protozoans
Discovered organisms
Below: Pediastrum (high power)
Below: Vorticella (medium power)
Below: rotifer (medium power)
Below: active rotifer (medium power)
Below: Cyanobacteria (high power)
Below: diatom (medium power)
Below: Spirogyra (medium power)
Pond food web
Lab questions
2. Finding, identifying, and taking a picture of protista was hard because they are extremely small and fast. Using a microscope on high power and trying to pinpoint a quickly moving organism was really difficult.
3. The Pediastrum was the most interesting organism that I found. It was interesting because it is in the algae genus, but it almost looked like it could be a protozoan. It didn't move, though, which was also intriguing.
4. The rotifer seemed to move by contorting its body into a compact shape and then shooting a pseudopod out in front to pull itself along.
5. Algae are the base of the food web in a pond. They photosynthesize, making food for themselves, but they also feed other organisms, including vorticella.