Name:______Date: ______Block: ______

The Cycling of Materials Keystone Webquest

BIO.B.4.2.3 Describe how matter recycles through an ecosystem (i.e., water cycle, carbon cycle, oxygen cycle, and nitrogen cycle).

When scientists talk about cycles, they are talking about sequences of events that repeat themselves. In the ecosystem, cycles can be very complex. There are many different types of elements and nutrients that must cycle for the ecosystem may function properly. These elements cannot be made or destroyed, but they can change their location. In this way, elements cycle through ecosystems. These cycles are called biogeochemical cycles.This webquest examines three of those cycles: water, carbon, and nitrogen.

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Label the steps of the WATER CYCLE here:

1. What are 3 states of matter water goes through during the water cycle?
2. How does water vapor get into the atmosphere?
3. What occurs during transpiration?
4. What occurs during condensation?
5. Where does the water that infiltrates (seeps) into the ground end up?

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Label the steps of the CARBON CYCLE here:

* THE CARBON CYCLE MAY BE CALLED THE OXYGEN CYCLE ON THE KEYSTONE!!**

Go to:

  1. Click on the arrow button to advance through the animation.
  2. Answer the following questions as you proceed through the animation.

1. How much carbon dioxide is in the atmosphere?
2. What are the top 3 gases that make up the majority of the atmosphere?
3. What happens to carbon dioxide during photosynthesis?
4. How do organisms other than plants get their carbon?
5. During respiration, what happens to carbon dioxide?
6. What are two examples of decomposers? What happens to carbon dioxide during decomposition?
7. What role does the ocean play in the carbon cycle?
8. What are the three fossil fuels?
9. What happens to carbon dioxide when fossil fuels (or any materials) are burned?

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Label the steps of the NITROGEN CYCLE here:

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  1. Click “Play Video”
  2. When finished, click “Close” in the upper right hand corner
  3. Click on “Test Yourself”
  4. Take the quiz, and record your score in the box to the right.
  5. Review your answers, and record the correct answers below.

1. What is the nitrogen cycle?
2. How do humans (or any animals) get nitrogen?
3. Which of the following comes first in the process of nitrification?
4. How do nitrates turn back into nitrogen gas?
5. Which of the following is one of the key components of the nitrogen cycle?
6. What do plants and animals use nitrates for?
7. How are people upsetting the nitrogen cycle?