Kingdom Protista

1. Any organism not classified as a—plant, animal, fungus, or bacteria (prokaryote).

2. Protists are eukaryotic having a distinct nucleus and organelles.

3. Most protists are unicellular (one-celled) but some are multicellular.

General Characteristics

4. Protists are primarily classified according to how they obtain nutrition:

a. Animal-like—heterotrophs (eat other organisms)

b. Plant-like—autotrophs They contain chloroplasts and make their own food (photosynthesis).

b. Fungus-like—Decomposers/Heterotrophs

Didinium

Parameciumeating

Green like plants!

Water mold

Animal-like Protists (Protozoans)1. Method of Movement:

a. Cilia—hair-like projections used for movement and feeding

b. Cytoplasmic streaming—pseudopod (false foot) extends and cytoplasm streams into it.

Video

Video

2. Paramecium:

Nucleus

Cilia

Cell Membrane

Contractile VacuoleCollects and removes excess H2O (Maintains homeostasis)

Oral GrooveUsed to collect food

3. Amoeba:

Nucleus

Contractile Vacuole

Pseudopod(False foot)

4. Importance of Animal-like Protists:

a. Harmful

i. Disease-causing parasites spread by insect bites

1. Malaria—Plasmodium spread by mosquito

2. African Sleeping Sickness— Trypmosoma

spread by Tsetse fly

Video 2:56

b. Beneficial

i. Recycles nutrients by breaking down dead matter

ii. Food source—for other organisms

iii. Mutualism—both organisms benefit

Example: Trichonympha—makes it possible for termites to eat wood. Termites do not have

the enzymes to digest wood.

Plant-like Protists1. Method of Movement:

a. Flagellum—whip-like structure used for movement

2. Euglena:

Nucleus

Contractile Vacuole

Chloroplasts

Flagella

Eyespot For photosynthesis (light)

Video

3. Unicellular Algae:

a. Phytoplankton provides a source of nourishment for other organisms

b. Protists recycle sewage and waste materials.

C. Algal blooms are harmful when overgrown—deplete water of nutrients consequently killing fish.

Algal blooms called Red Tides cause illness, paralysis, and death of fish and even humans.

4. Multicellular Algae:

a. Examples---

i. Red Algaeii. Green Algaeiii. Brown Algae

5. Uses of Algae:

a. Algae is a good food source for life in the oceans.

b. Algae produces much of Earth’s oxygen through photosynthesis.

c. Algae is used to make sushi, ice cream, salad dressing, plastics, paint, agar.

Fungus-like Protists:

1. Examples—

a. Slime molds

b. Water molds

2. Importance of Fungus-like Protists:

a. Beneficial—Recycles dead organic material. Results in rich, topsoil providing nutrients for plants.

b. Harmful—

P. Infestans (water mold) caused Great Potato Famine in Ireland. This lead to the mass starvation of 1 million Irish people.