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  Teaching Guide
Activity 2: Grades 5-8
Nutrient Depletion

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  1. What happened to the level of soil nutrients over time?
    (The nutrient level dropped as the experiment progressed.Students should be able to provide evidence through their data)
  2. What might have caused the observed change in nutrients? (The plant removed the nutrients from the soil and incorporated these essential chemicals into new plant tissue.)
  3. Was there a difference in the nutrient level from samples taken from between the root system and those taken outside the root system? Explain.
    (Accept all reasonable replies such as after the first two-week period there was a noticeable difference. After four weeks the difference was less obvious. The nutrients were quickly drained from areas in contact with the growing rootlet system. As the plant grew, the roots spread into the soil. In addition, watering the plants transported nutrients to the regions of the soil that were in contact with roots.)

The activities in this guide were contributed by Michael DiSpezio, a Massachusetts-based science writer and author of "Critical Thinking Puzzles" and "Awesome Experiments in Light & Sound" (Sterling Publishing Co., NY).

Academic Advisors for this Guide:
Corrine Lowen, Science Department, Wayland Public Schools, Wayland, MA
Suzanne Panico, Science Teacher Mentor, Cambridge Public Schools, Cambridge, MA
Anne E. Jones, Science Department, Wayland Middle School, Wayland, MA

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