| Students will view progress of their biofilm formation and view biofilm form ing organisms from other environments.
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| Objectives |
The student will be able to;
1. Define: biofilm, biodiversity, 2. Identify various niches within an
ecosystem, 3. Explain how organisms within the ecosystem depend on one
another, 4. Describe the benefits and limitations of the ecosystem
model, and 5. Develop an appropriate experimental design that tests for
biofilm formation in a
simple ecosystem model.
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| Materials |
Model aquatic ecosystems designed by teams
Website of other biofilm forming organisms
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| Procedure |
Explanation 1 (Post-Lab, Day 1)
View various biofilm websites, in particular those associated with Maryland Sea Grant (www.mdsg.umd.edu/Education/biofilm/), in order to see other organisms found in biofilm formations.
Explanation 2 (Day 2, One week later)
1. Use the Television/Flex Cam/video microscope set-up to view slides from several of the ecosystem models.
2. Once students have viewed the slides and observed biofilm formation, address questions pertaining to the source or sources of the organisms within the biofilm. With the ecosystem model containing all of the components of an ecosystem, which biotic or abiotic factor is responsible for the biofilm organisms?
3. Distribute graphic organizers that will assist students in designing an experiment to test for the source of the biofilm organisms.
4. Students brainstorm possible tests. Examples include limiting biotic factors (only one type of biotic factor within the ecosystem model) or changing abiotic factors (temperature, light, type of water, etc.
5. Have students address the components of their experimental designs, accounting for independent and dependent variables, as well as factors to keep constant. Students may make modifications at this point to their ecosystem model.
6. Design a chart that could be used to record data from this investigation.
7. Use student designs to conduct tests for biofilm formation.
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| References |
Maryland Sea Grant
Biofilms and Biodiversity, http://www.mdsg.umd.edu/Education/biofilm/
American Society for Microbiology - easy to do
Microbial Slime, http://www.microbe.org/experiment/biofilms.asp
American Biology Teacher - more advanced
Aquarium Culture of Freshwater Invertebrates by Timothy S. Wood
(The American Biology Teacher, vol. 58, January 1996).
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| State
Standards |
3.5.1- The student will analyze the relationships between biotic diversity and abiotic factors in environments and the resulting influence on ecosystems.
3.5.2- The student will analyze the interrelationships and interdependencies among different organisms and explain how these relationships contribute to the stabilty of the ecosystem.
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| Lesson Resources |
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