What is a Protist? A Look into the “Grab Bag” Kingdom

What is a Protist? Eukaryotes that cannot be classified as animals, plants, or fungi. All live in moist surroundings. Most are unicellular but some are multicellular. Some are heterotrophs, autotrophs, or both. Some cannot move, while others zoom around.

Animal-Like Protists Are heterotrophs that move from place to place to obtain food. AKA: Protozoans: unicellular animal-like protists that are classified into 4 groups: 1. Pseudopods 2. Cilia 3. Flagella 4. Parasites

Amoeba Moves and obtains food using a pseudopod: temporary bulge of the cell. “False Foot” Form when the cytoplasm flows toward one location and the rest of the organism follows. Use to trap food.

Paramecium Move and obtain food using cilia: hairlike projections that move in a wavelike motion. Movement of cilia sweeps food into organism. 2 nuclei: large controls all functions. Small only reproduction. Reproduce by binary fission: or splitting apart.

Plant-Like Protists Commonly called algae. Autotrophs. Much of the Earth’s oxygen is made by algae. Vary greatly in size.

Euglena Green, unicellular algae When sunlight is present= autotroph, but can be a heterotroph. Move using Flagellum Eyespot: sensitive to light and helps euglena recognize the direction of a light source.

Green Algae/Volvox Closely related to plants. Contain chlorophyll. Diverse. Volvox live in colonies and are the most plant-like of all the green algae.

Other Plant-Like Protists Brown Algae: seaweed and kelp Diatoms: good source of food for fish Dinoflagellates: light up ocean’s surface when disturbed by a boat. Allow fighter jets to land on carriers at night.