Protists

1. Protists Pgs. 46 - 56

2. General Characteristics All are eukaryotic (have a cell nucleus). Most are single-celled. Some are producers and use photosynthesis. Others are consumers and grouped by how they obtain energy. They can be fungus-like, plant-like, or animal like.

3. Fungus-like Protists They gain nutrients from dead organic matter by secreting digestive juices into the food source and then absorb nutrients. They also reproduce like fungi. There are two types: Slime molds and water molds.

4. Slime molds They are thin masses of living matter. They are colorful, shapeless globs. Typically, they live in cool, shady, and moist places in the woods and fresh water. Most of the time they are single-celled, but can come together and function as a single organism.

5. Slime Mold Diet and Reproduction Diet includes bacteria, yeast, and small bits of decaying matter. They eat by surrounding food particles and digesting them. Slime molds reproduce by developing stalklike structures with round knobs. The knobs contain spores that can survive and develop new slime molds.

6. Water Mold Water molds are small fungus-like protists. They live in water, moist soil and other organisms. Some are decomposers, others are parasites. Their hosts include plants, animals, algae or fungi. Some cause diseases that attack potatoes and grapes.

7. Plantlike Protists: Algae Producer protists that go through photosynthesis are algae. They all have chlorophyll, a green pigment, but some have other pigments. Multicellular algae lives in shallow water and are known as are seaweed or kelp.

8. Single-celled algae All need to be viewed with a microscope. Single-celled algae are phytoplankton Phytoplankton are producers that provide food for other water organisms and produce oxygen. They are divided based on their color and cell structure. These are red algae, brown algae, green algae, diatoms, dinoflagellates, and euglenoids.

9. Red Algae This is most of the world’s algae. They contain a red pigment and live in tropical marine waters. The red pigment allows them to absorb light that filters into deep clear water. They can be as long as 260m but are usually less than 1 meter long.

10. Brown Algae Brown algae is found in cool waters. They are very large, about 60m or more, and attach to rocks. They have chlorophyll and a yellow-brown pigment.

11. Green Algae The most diverse group of algae. They have mostly chlorophyll as their main pigment color. Most are found living in water, but can be in soil, snow, trees, or other organisms. Individual cells can live in groups called colonies.

12. Diatoms Single celled organisms found in fresh and salt water. Use photosynthesis to make food. They have unusual shapes. Their cell walls are made of cellulose and silica. Each cell is enclosed in a shell of two parts. Their remains are used in silver polish, toothpaste, and insulation

14. Dinoflagellates Dinoflagellates are single-celled algae that live mostly in salt water . They have two whiplike strands called flagella that allow them to move through the water. Most are producers, but some are consumers, decomposers or even parasites. Some are red and produce a poison. If overpopulated it creates a red tide

16. Euglenoids Single celled-protists that live primarily in fresh water. They are both plants and animals. They use photosynthesis or consume animal when light is low. They have flagella

18. Animal-like Protists They are single-celled consumers typically known as protozoa. They are grouped as amoebalike protists, flagellates, ciliates, and spore-forming protists.

19. Amoebalike protists A soft, jellylike protozoan found in fresh or salt water, soil or in animals as parasites. They have contractile vacuoles that allow them to get rid of excess water. They move with psuedopodia (false feet).

20. Feeding Amoebas They feed by engulfing food. They surround food and form a food vacuole where enzymes can break down the food. The nutrients needed are absorbed into the cytoplasm. Wastes are removed by reversing the feeding process.

21. Protozoa with Shells Some amoebalike protozoa have an outer shell. They are called Radiolarians and have silica shells that make them look like ornaments Others are Foraminiferans and have snail-like shells of calcium carbonate.

23. Flagellates Protozoa that use flagella to move. They live in water or as parasites. The Giardialamblia is one parasite that lives in humans. Some live in symbiosis with other animals. One example is termites. Flagellates help digest cellulose in the wood they eat.

24. Ciliates The most complex protozoa that have hundreds of tiny hairlike structures called cilia. Cilia help the protozoa move and feed. A common ciliate is a Paramecium They have two types of nuclei: macronucleus and micronucleus. Macronucleus: controls cells functions Micronucleus: passes down genetic material during reproduction

26. Spore forming Protists All parasites that absorb nutrients from their hosts. They have no flagella or cilia and cannot move on their own. They have a complicated life cycle. Plamodiumvivax is the protists that causes malaria

28. Reproduction of Protists Some reproduce asexually, where the offspring come from one parent. Amoebas and plantlike Euglena reproduce asexually. Some reproduce sexually requiring two parents.

29. Conjugation In conjugation, two Protist parents join together and exchange genetic material and then divide into four new offspring with new combinations of genetic material.