Protozoans and Algae Copyright 2000 BioMEDIA ASSOCIATES

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1 Protozoans and Algae Study Guide, 1 Eye of the Cyclops Video Series Teaching Guides Protozoans and Algae Copyright 2000 BioMEDIA ASSOCIATES Environment: a freshwater pond Habitat: the shallows Permission is given to copy or print this guide for use within institutions that have purchased the Protozoans and Algae video program. All images are property of BioMEDIA ASSOCIATES and cannot be resold without permission. Contents of this guide... About the organisms from Protozoans and Algae page 3... Teacher s guide to Protozoans and Algae page 6... Student Research Problems page Protist Gallery page In this episode... Back into the weedy shallows, the crew is amazed at the diversity of protozoans swimming by the observation ports. They set about filming a variety of single-celled organisms: some that live attached to the plant stems, and others with green algae cells that are the primary food source for the pond s larger herbivores. The adventure is followed by documentary video featuring pond ciliates, flagellates and amoebas.

2 Cyclops Vehicle Dimensions LENGTH 1 mm BEAM.65 mm Protozoans and Algae Study Guide, 2 Vehicle Mission Maximum speed Maximum depth Mission duration 10 centimeters per minute 2.5 meters 50 days The microsubmersible Cyclops is designed for extended exploration of freshwater ponds and streams. The vehicle carries a crew of four. There are two onboard auxilary craft: a diving bell and a terrestrial crawler (disassembled). Imagine what the pond environment looks like to these explorers (only 50 microns tall). What unique problems might the crew encounter? How would they acquire building materials, such as glass? Where would they find fuel and oxygen? engine room airlock observation/pilothouse diving room diving bell laboratory bunkhouse emergency escape hatch storage modules grabber claws Eye of the Cyclops vehicles are designed by Eric Robert Russell/Castle Builders Entertainment

3 About the Organisms What are protozoans and algae? Protozoans and Algae Study Guide, 3 Protozoans and algae are general names given to the complex single celled life one finds in ponds and wetlands. They are cells that have a nucleus and cellular organelles. Bacteria, the other branch of single celled life, are much simpler cells. Bacteria are cells without nuclei. On the tree of life, protozoans and algae are much more closely related to animals and plants than are bacteria. In this Cyclops episode the crew attempts to film the protozoans and algae encountered as they travel a few centimeters through the weedy shallows of their pond. This is a log of what they found. Vorticella is a ciliated protozoan that attaches to objects in the water by a contractile stalk. Vorticellids are found in clusters often large enough to be visible to the naked eye. Gonium is a simple colony made up of identical cells. Gonium is photosynthetic, getting its energy from light. Euplotes is a ciliate that uses tendril-like structures (fused cilia called cirri ) to walk over surfaces. Euplotes feeds on small green cells (Chlamydomonas) holding them in its food trap prior to engulfment. Spirogyra is a common thread alga made up of chains of cells, each with a spiraling chloroplast and clearly visible nucleus. Illustration of Spirogyra reproducing

4 Protozoans and Algae Study Guide, 4 More Organisms... Urocentrum turbo is a ciliated protozoan that remains in its feeding station by producing a very thin tether too thin to see with a light microscope. Diatoms are algae cells that have yellow pigments and a surrounding house made from silica glass. Amoeba moves and engulfs food by cell extensions called pseudopodia. There are many different kinds of amoebas, some very tiny, others large enough to see with the naked eye. Arcella is one of many kinds of amoebas that produce shells. Peranema is a flagellated protozoan that uses the tip of its flagellum like a propeller. Euglena is a photosynthetic flagellate. There are many kinds (species) of euglinids found in virtually all aquatic environments.

5 Protozoans and Algae Study Guide, 5 More Organisms... Bursaria a giant cell easily visible to the naked eye. Bursaria travels mouth first, engulfing smaller cells in its path. Paramecium bursaria, the green paramecium, is filled with symbiotic algae cells. The algae make food molecules by photosynthesis and share some of these products with their host. Paramecium provides its small green guests with the raw materials needed for photosynthesis, and a relatively safe environment in which to live. Illustration of Paramecium caudatum Watercolor illustrations of microorganisms courtesy of the artist, Leslie Russell The ten-minute Observation Log gives detailed information on some of the organisms encountered by the Cyclops along with some of their relatives. The organisms are all seen in natural time. In the final observation section (without narration) see if you and your students can find the two protozoans not seen by Cyclops. Perhaps you can identify them using the reference book listed on page 8.

6 Protozoans and Algae Study Guide, 6 Teacher s Guide Use the Protozoans and Algae video to excite your students with the idea of visiting a local pond or wetland in order to discover and study single celled life forms, and through these activities to better understand the ecology of these habitats. Relevant National Science Education Standards Grades 5-8 Reproduction and Heredity - Reproduction is a characteristic of all living systems; because no individual organism lives forever, reproduction is essential to the continuation of every species. Some organisms reproduce asexually. Other organisms reproduce sexually. Protozoans and algae are wonderful subjects for observing biological reproduction. See how many examples of reproduction can be found in the video program. Regulation and Behavior - Behavior is one kind of response an organism can make to an internal or environmental stimulus. A behavioral response requires coordination and communication at many levels, including cells, organ systems, and whole organisms. Behavioral response is a set of actions determined in part by heredity and in part from experience. Protozoans respond to their environment. Examine Paramecium to see how it responds to obstacles in its path, and to food. Populations and Ecosystems - Populations of organisms can be categorized by the function they serve in an ecosystem. Plants and some micro-organisms are producers they make their own food. All animals, including humans, are consumers, which obtain food by eating other organisms. Decomposers, primarily bacteria and fungi, are consumers that use waste materials and dead organisms for food. Food webs identify the relationships among producers, consumers, and decomposers in an ecosystem. - Identify each organism found by the Cyclops crew as producer, decomposer, scavenger, predator. For ecosystems, the major source of energy is sunlight. Energy entering ecosystems as sunlight is transferred by producers into chemical energy through photosynthesis. That energy then passes from organism to organism in food webs. Diagram a food web that relies on single celled life. Diversity and Adaptations of Organisms grades Biological evolution accounts for the diversity of species developed through gradual processes over many generations. Species acquire many of their unique characteristics through biological adaptation, which involves the selection of naturally occurring variations in populations. Biological adaptations include changes in structures, behaviors, or physiology that enhance survival and reproductive success in a particular environment. What adaptations (structures or behaviors that function to promote the organism s survival ) can be listed for the organisms found by Cyclops?

7 Protozoans and Algae Study Guide, 7 Concept Words used in this Lesson Habitat: The place where an organism lives. Microorganisms : Small living things that can only be adequately observed with the aid of magnification. Macroorganisms: Organisms that can seen without magnification (although enlargement may be needed to see their structures) Algae: Common name for photosynthetic organisms other than plants. Protozoans: The common name for independently living nucleated cells that are not photosynthetic. (although some very active green cells, such as Euglena, are often called protozoans) Protists: A general term used to describe all kinds of independently living, nucleated cells and their multicellular relatives. Cilia: Short hair-like organelles on the surface of protozoans that beat against the water producing locomotion and feeding currents. Flagella: Long whips, used in various ways to propel flagellated protists through the water. Cilia and flagella have the same molecular make up. Pseudopodia: false feet are projections used by amoeboid protists to move over surfaces and to surround and engulf food. Observational and informational resources Books: Rainis and Russell, Guide to Microlife, Franklin Watts Publisher (identification, color photos, and life descriptions of common forms of microlife including plankton) Golden Book of Ponds Videos: The Small Life of Ponds and Wetlands, BioMEDIA ASSOCIATES CD-ROMs: The Wetlands Explorer, BioMEDIA ASSOCIATES

8 Protozoans and Algae Study Guide, 8 Programs in the Eye of the Cyclops series Plankton Play (15 minutes) Cyclops and its intrepid crew of explorers dive into open water where they encounter the denizens of the plankton: micro-crustaceans, insects, rotifers and protists, all showing unique adaptations for open water life. Decomposers Everywhere (15 minutes) Settling their craft into the bottom, the micronauts discover that the bottom ooze is populated by bacteria, the microbes that decompose and recycle organic materials an unforgettable visual introduction to living bacteria. Food Chains Begin with Photosynthesis (15 minutes) In this episode, a single algae cell is rescued and its green secrets revealed through experiments performed on board the Cyclops. They discover how algae start food chains that ultimately sustains the fish, birds, amphibians and mammals living in and around the pond. Protozoans and Algae (15 minutes) Cruising through the weedy shallows, the crew is amazed at the diversity of protozoans swimming by the observation ports. They discovery how these complex single cells feed, reproduce and escape. Predators of the Shallows (15 minutes) While engrossed in observing the food capturing and feeding methods used by predatory flatworms, the Cyclops crew becomes trapped by the tentacles of Hydra where they receive a visible lesson in the process of digestion. White Water Adventure (15 minutes) Trying to return to duck weed base, the Cyclops is channeled into the pond outlet, where they tumble into a rapidly flowing stream and discover a world of aquatic insects adapted for life in flowing water. Discovering a Forest Microcosm (15 minutes) Washed onto a sand bar, the Cyclops crew assembles their terra-rover and discovers a world dominated by mites, roundworms, tiny insects, bacteria and fungi creating a forest floor ecosystem on which the trees depend. Backyard Biodiversity (15 minutes) The micronauts discover that gardens support an amazing community of small life including butterflies and their larva, pollinating insects, herbivores, predators, scavengers and earthworms that constantly process the soil. Visit Cyclops on the World Wide Web Check for an ongoing story of the crew s biological explorations and more tips on how to study the fascinating organisms they encounter. Post your research results there and see what other students are discovering. Eye of the Cyclops is produced by BioMEDIA ASSOCIATES in association with Castle Builders Entertainment. Order Eye of the Cyclops from ebiomedia P.O. Box 1234 Beaufort, SC ORDER/INFO: (877) /(843) FAX: (843)

9 Teacher s Key to Organisms Protozoans and Algae Study Guide, 9 Spirogyra 1 anterior end 1 Paramecium 1. contractile vacuole 2. oral groove 3. macronucleus 4. micronucleus 5. cilia 6. lysosomes 1. zygote 2. conjugating strands 3. conjugation tube 4. spirogyra filament 5. chloroplast 6. nucleus Euglena 6 5 posterior end 1. nucleus 2. stigma (eyespot) 3. chloroplast 4. mitochondrion 5. locomotor flagellum Amoeba 6 1. advancing speudopodium 2. granular endoplasm 3. food vacuole 4. ectoplasm 5. nucleus 6. contractile vacuole

10 Student Research Protozoans and Algae Study Guide, 10 Pond water Look but don t drink: If you collect jars of pond water, adding in some decomposing plant material from the pond bottom, you will find many of these organisms along with others. Collect from different habitats in the pond and from different natural water sources and see what you can discover. One of the ways to increase the numbers of protozoans living in your collections is to keep your collection in a warm room (but away from direct sunlight) for several days. Under these conditions many kinds of protozoans will reproduce rapidly giving you a better chance of finding them in sample. Naked eye observation: Use a flashlight or desk lamp held at an angle behind the culture jar while you look through the jar at a dark background a technique called back-lighting. Often you will be able to see tiny specks swimming through he water but only if lit from behind. Be careful not to shake the jar and disrupt the various kinds of protozoans that have settled into microhabitats in the culture. Use an eyedropper to pick up any large cells, or swarms of smaller cells for microscopic examination. Tips for microscope viewing of protozoans and algae: If a DiscoveryScope or stereo dissecting microscope is available you can travel into the magical world of microspace. Using back-lighting, magnification of 10X to 20X is plenty for observing most large protozoans. The wide field of view you get using these instruments is great for observing behavior like watching a football game from the stands. Using a microscope is like watching the same game through a powerful telescope; all you might see during a play is someone s number. When you want to examine the cell structure of a protozoan there is no substitute for a laboratory microscope. Always start a hunt with the widest field objective lens (lowest magnification). When hunting, remember that these cells are very transparent, and so difficult to see. One trick is to increase contrast by closing the iris. To understand the best ways to use a microscope for viewing living cells, see the video program Imaging a Hidden World, available from Project: A local survey of protozoans and algae. Assume you have just landed on Earth from another world. Your assignment is to survey and report on the single celled life found in your survey area. Send out collectors. Assign researchers to examine samples. Identify your specimens. Compile your report.

11 Protist Gallery Protozoans and Algae Study Guide, 11 These organisms were collected from a small pond using a plankton net. As a biologist interested in classification, organize this set into groups of protozoans and groups of algae All images 2000 BioMEDIA ASSOCIATES 6 9 Photography by Bruce J. Russell