Mr. Bouyer - Day 3 - 4

The Kingdom Protista contains the protozoa, algae, slime molds, and water molds. All of these organisms are eukaryotic and lack tissue differentiation.

Protozoa

These single-celled microorganisms are noted for their ability to move independently. Protozoans live in environments that vary from soil to the bodies of other organisms. Many species make up zooplankton, one of the primary sources of energy in aquatic ecosystems.

The microscopic life in a freshwater pondis some of the most diverse life on Earth.

The phyla of protozoa:

• Sarcodina - the amoeba
• Ciliophora - the paramecium
• Zoomastigina - the trypanosoma
• Sporozoa - the plasmodium

These plant-like protists all carry on photosynthesis. Although most algae are single-cell organisms, some are large multicellular organisms. The largest algae are the seaweeds known as kelp that are hundreds of feet long. All algae, no matter their size, lack tissue differentiation. Most aquatic algae compose the phytoplankton, the foundation of aquatic food chains. Phytoplankton produces almost half the world's carbohydrates and oxygen.

The phyla of algae:

• Chlorophyta - the green algae
• Phaeophyta - the brown algae
• Rhodophyta - the red algae
• Bacillariophyta - the diatoms
• Dinoflagellata - the dinoflagellates
• Chrysophyta - the golden algae
• Euglenophyta - the euglenoids (both pictures on this page)

These heterotrophic organisms spend a part of their lives in a mobile, amoeba-like form. They produce a reproductive structure that makes them look like a fungus. They appear as a glistening, viscous mass of slime. Most are yellow or red, but some are white.

The phyla of slime molds:

Acrasiomycota - pseudopasmodium
Myxomycota - plasmodium

Fungus-like organisms composed of branching filaments of cells. While most water molds are aquatic, some live in the soil, and others are plant parasites.

The phyla of water molds:

Oomycota - plant parasites responsible for blight.
Chytridiomycota - aquatic protists very similar to fungi.

The body structure, reproduction, and biochemical pathways cause biologists to think that chytrids are a link between protists and fungi.

Oral Presentation 114:
Presentation must be ready at the beginning of class tomorrow to receive credit for this assignment.

1. Choose either a species of protozoa or algae. Find a quality website with information about the organism.
2. Tell your science facilitator the name as soon as you have chosen.
   Important: a species can be used by only one person. This is on a first come, first served basis. The first person to give the name to the science facilitator gets the organism.
3. Write a one paragraph summary of the information about this organism and write the URL for the website on your paper.
4. Tomorrow in class, you will use your summary to tell the class about the organism. Be sure to include something interesting about the organism.

Your science facilitator will grade your oral presentation using the criteria marked with a red checkmark on this science presentation grade rubric.
Give the paragraph to your science facilitator after your presentation.

Research Links:

• Pond Life Identification - Microscope Magazine
• Protozoa - Glasgow University
• Protista Links - The Protist Information Server
• Links to all the Eukaryotes - U of California at Berkeley
• Phytoplankton Ecology - Lund University
• Microscopic Organisms in a Freshwater Pond - Microscopy-UK

The Fungi

The Kingdom Protista was the third kingdom named. At the time, the other two kingdoms were for animals or plants. Some scientists wanted to include these organisms in the plant kingdom and others protested and wanted to place them in the animal kingdom. Eventually, a compromise was reached. They were all placed into a third kingdom, the Protists.