1. Interactions Within Ecosystems Grade 7 Unit

2. Overview of Remaining Unit  Ecological Pyramids  Building 3D models - lab  Pesticides : Poison in Food Chain  Water Cycle  Landfill – Lab  Choosing a waste disposal site  Garbage and the community  Acid in water  Greenhouse simulation - lab

3. Assessment  Labs – 30%  3D model  Landfill  Greenhouse simulation  Debate – 15%  Notebook – 10%  Quiz – 15%

4. Scientific Report  Purpose: Why are you doing the experiment? What are you trying to learn?  Hypothesis : What do you believe will happen? Be specific.  Materials : List all materials needed to complete the experiment  Observations: Charts, pictures, and words describing what you see, feel or measure  Conclusion: What did you learn in the end? Be specific and relate to the purpose. Write a sentence on whether or not your hypothesis was accurate.

5. Ecological Pyramids

6. Transfer of Energy

7. Rule of 10  Each time energy is transferred within an ecosystem, some of the energy is lost.  Ex. When mosquitoes take a bite from you it stores very little of the energy available in your blood.  Most of the energy is used to survive. Flight alone requires a tremendous amount of energy.

8. Dragonflies vs Mosquitoes  When a Dragonfly eats a mosquito, only about 10% of the energy that came from your blood is passed to the dragonfly.  The Dragonfly uses energy in catching the mosquito, eating it, and breaking down the large food molecules to simple nutrients.  This means only a very small fraction of the energy from your blood is stored by the dragonfly.

9. Food Chains in a Graph  Ecological Pyramids are a graphical way to show the effects of loss of energy.  Each level in a pyramid matches a level of producer or consumer in an ecosystem or food chain.  At each level the amount of energy available is less.  The # of organisms at each level of the pyramid usually decreases.

10. Understanding  1. Why is less than 10% of the energy the mosquito gets from its food transferred to the dragonfly?  2. Using your own words, explain why there are usually more producers in an ecosystem than consumers?