Protists I & II Lab 4 BIOL 171 Remember!: Classification System Saving for next week. Yep. We’ll be looking at all of these! Ancestral Eukaryote Protists are everywhere in Eukarya! “the junk drawer of the eukaryotes” We’ll be looking at all of these! Ancestral Eukaryote Protists are everywhere in Eukarya! “the junk drawer of the eukaryotes” 6 Kingdoms • • • • • • Plants (Plantae) Animals (Animalia) Fungi (Fungi) Eubacteria Archaeabacteria Protista These are considered “qualitative” terms— not correct science terminology. A constantly changing system… Linnaeus[5] Haeckel[6] (1735) (1866) 2 kingdoms 3 kingdoms Animalia Vegetabilia Chatton[7] (1925) 2 groups Animalia Plantae Eukaryote Copeland[8] Whittaker[2] Woese [9][10] (1938) (1969) (1977,1990) 4 kingdoms 5 kingdoms 3 domains Animalia Animalia Plantae Plantae Protoctista (not treated) Protista Prokaryote Monera Fungi Eukarya Protista Monera Archaea Bacteria Lab Study:Trichonympha Excavata - Parabasalids • Lives in the intestine of the termite • Bacterial endosymbionts inside Trichonympha digest cellulose - Termite > Trichonympha > Spirochetes Procedure 1. 2. 3. 4. 5. 6. Place a couple of drops of Ringer’s solution on a clean slide. Transfer a termite into the drop of solution. Place slide under a dissecting microscope. Place the tips of dissecting needles at either end of the termite and pull in opposite directions. Locate the long tube that is the termite’s intestine. Place a cover slip over the specimen and lightly press down on coverslip to release the Trichonympha from the intestines. Observe with a compound microscope. Lab Study A: Excavata - Euglenozoans Trypanosoma and red blood cells Lab Study B: Alveolates Dinoflagellates: mixed dinoflagellates (live & wet mount), and Peridinium (wet mount) not in manual Ciliates: Paramecium caudatum – (wet mount) in manual Dinoflaggelates Paramecium structures Lab Study C: Stramenopiles Diatoms (Bacillariophyta) – make wet mount Also observe diatomaceous earth (the cell wall deposits from diatoms) – make wet mount and look at prepared slides Diatom diversity Diatom cell wall made of silica Stramenopile flagella Brown Algae (Phaeophyta) Living: Ectocarpus and Sphacelaria Preserved: Fucus and Laminaria Lab Study D: Rhizaria (different title from manual) • Foraminiferans - prepared slides • Radiolarians – prepared slides Foraminiferans (forams) - prepared slides Radiolarians - prepared slides Amoebozoans…. Hang in there. Lab Study E: Amoebozoans Amoeba proteus • Pseudopodia – temporary extensions of amoeboid cells, function in moving and engulfing food Lab Study E (still): Slime Molds (Mycetozoa) • Protists which use spores to reproduce • Heterotrophic – requires carbon in organic form, cannot manufacture its own • Feed using phagocytosis • Suggests they descended from unicellular amoeba-like organisms • Two types: plasmodial and cellular (we will be observing plasmodial type today) Physarum (slime mold) • Plasmodial stage – vegetative stage that consists of a multinucleate mass of protoplasm (no cell walls), feeds on bacteria as it creeps along the surface of moist logs or dead leaves • Fruiting bodies – reproductive structures that produce spores Physarum (plasmodial stage) Is slime mold smarter than Japan's railway engineers? check it out! Slime Mold Life Cycle Think about… • • • • • • Morphological characteristics Ecology of the organism How does the organism get around? What role do they play in the ecosystem? Do they have any economic value? Where do they live? • Don’t know the answer?? It’s probably a great research question! Ask me about it. Protists 2 Laboratory 4 (still) BIOL 171 What is red algae? • • • • • Eukaryotic Photosynthetic Mostly multicellular NOT plants Most are aquatic Lab Study F: Red Algae (Rhodophyta) • Simplest is single-celled, but most have a macroscopic, multicellular body form • Autotrophic (photosynthetic)– manufactures its own organic nutrients from inorganic carbon sources • Contain chlorophyll a and accessory pigments phycocyanin and phycoerythrin • Not all are red! Many green, black, even blue, depending on the depth in the ocean they grow Living Specimens Porphyridium Preserved specimens Porphyra coralline algae Chondrus crispus Porphyra life cycle both sexual and asexual – alternation of generations! Coralline algae – “living rock” • Extremely important role in the ecology of coral reefs: sea urchins, fish, and mollusks eat them (herbivore enhancement). • Create microhabitats that protect invertebrates from predation. • Cell walls composed of calcium carbonate – this allows it to fossilize • Economic importance: soil conditioners, food additive for livestock, water filtration, medical vermifuge (stopped late in 18th century), preparation of dental bone implants Economic Uses • Agar – polysaccharide extracted from the cell wall of red algae, used to grow bacteria and fungi • Carrageenan – extracted from red algae cell walls, used to give the texture of thickness and richness to foods such as dairy drinks and soups. • Porphyra (or nori) – seaweed wrappers for sushi, billion-dollar industry! Lab Study G: Green Algae (Chlorophyta) • unicellular motile and non-motile, colonial, filamentous, and multicellular – GREAT DIVERSITY • Live primarily in freshwater • Share many characteristics with land plants – Storage of starch, presence of chlorophylls a and b, photosynthetic pathways, and organic compounds called flavonoids • Most botanists support the hypothesis that plants evolved from green algae Living Specimens Chlamydomonas Volvox Pediastrum Closterium Pandorina Volvox Daughter colonies Preserved Specimens Ulva Chara Table 4: Representative Green Algae (pg. 72) Name Body Form Spirogyra Filamentous Ulva Leaf like Chara Branched Chlamydomonas Pandorina Unicellular flagellate Aggregate Volvox Colony (flagellate) Pediastrum Non-motile colony Closterium Non-motile single celled Characteristics Psychedelic slime mold video: