Fond of Ponds

Introduction: Most students have looked at microscopic organisms in pond water. In this lab students will be required not only to indentify organisms, but also construct food chains using the organisms they see. The class can share food chains and synthesize a food web. Food webs may be analized by the trophic levels. Finally, the studetns may be asked to show how human intervention affects this habitat. Materials: Ward’s Pond Water, microscope, slides, eyedropper Procedure: 1. Have students identify 9-12 organisms. 2. Classify the organisms as autotrophic or heterotrophic. 3. Construct a food chain. 4. Share food chains with other groups and construct a food web. 5. Identify the trophic levels. 6. Identify a pollutant source that might affect 2-4 organisms in the       food web. 7. Explain the consequences that the pollutant will have on the       food web.

Questions: What is alive? What is moving? What has color? Anything moving and have color? How can you tell if an organism is autotrophic or heterotrophic? What are two sources of pollutants in the watershed? Which of the organisms of your food web will be affected by the pollutant? How? Draw any two organisms.