Exploring the Nitrogen Cycle

Name ______Date ______Period ______Score ______

Do you recognize this symbol? It is the universal symbol for recycling, a continuous loop made up of spate but similar parts. Most people are familiar with the symbol found on blue or green bins, indicating where to dispose of recyclable materials.

  1. Make a list of Materials that can be recycled.
  1. Make a list of projects that are made from recycled materials.
  1. Think about the process involved in manufacturing new products for recycle materials.

You might be surprised to learn that the process of recycling is not just a human endeavor. Everything in nature is recycled, from the air we breathe to the water we drink. In fact, the amount of matter found on Earth today is essentially the same amount that existed on Earth a million years ago.

Through biological and geologic processes, this matter is not destroyed, but is changed from one form to another. Ultimately, the changes convert the matter back to its original form. Imagine a world where materials were not recycled; once something was made, it would never change. Many necessary materials would be used only once, and future generations would never be able to use them.

Fortunately, this is not the case. As you know, plants and animals decompose, freeing up nutrients to be used in other things. Also, humans ingest food and excrete waste. Our waste, however, is food for other organisms. They excrete waste, which in turn provides food for other organisms. Finally, the products are the plants and animals that humans eat. Thus, the cycle repeats. To function, these cycles require many different organisms as well as different abiotic mechanisms.

Things to think about:

  1. What happens if one of the steps in a cycle is missing?
  2. How do different organisms rely on each other to complete these cycles?
  3. Could there be a worldwide food shortage if certain bacteria disappear from the soil?

In this activity, your group will explore whether or not organisms can flourish without other organisms. You will take DAILY measurements of 1. Ammonia, 2.Nitrite, and 3. Nitrate to monitor the health of one type of organism: fish, bacteria, or plants. Think about the inputs and outputs of your aquarium and what is missing? This lab is a 3 Activity lab. (Fish, Bacteria and Plants) You will be required to collect data from each setup

Before the lab define the list of terms:

  1. Ammonium
  1. Nitrate
  1. Cyanobacteria
  1. Aerobic
  1. Anerobic
  1. Nitrogen Fixation
  1. Assimilation
  1. Ammonification
  1. Nitrification
  1. Denitfification
  1. Eutrophication
  1. Using the list of terms draw a nitrogen cycle

Fish Tank Activity:

Materials:

1

Exploring the Nitrogen Cycle

Name ______Date ______Period ______Score ______

1 gallon aquarium

¾ gallon of distilled water

5 fish

ammonia test strips

nitrite/nitrate test strips

fish food

1

Exploring the Nitrogen Cycle

Name ______Date ______Period ______Score ______

  1. Predict what will happen to the fish over the next several days. Will the ammonia, nitrite, or nitrate levels increase. (They will start at ZERO)What effect will this have on the fish?
  1. Set up a 1-gallon aquarium with about ¾ of gallon of distilled or conditioned tap water at your workstation.
  2. Add 5 fish to your aquarium.
  3. Following the directions on the bottles, measure the ammonia, nitrite, and nitrate levels in your aquarium. Record your results in data table.
  4. Feed the fish a very small amount of food; a small pinch containing 2 to 3 flakes is plenty.
  5. Repeat steps 4 and 5 on the next two days. Record your results and any behavioral changes in the fish. If any water is added or any fish are removed, record this as well.

TEST / DAY 1 / Day 2 / Day 3 / Day 4 / Day 5
Ammonia
Nitrite
Nitrate
Behavior of Fish / DAY 1 / Day 2 / Day 3 / Day 4 / Day 5

Additional observations or changes in lab:

Graph your results:

Bacteria Tank Activity:

Materials:

1

Exploring the Nitrogen Cycle

Name ______Date ______Period ______Score ______

1 gallon aquarium

¾ gallon of distilled water

aquarium pebbles

ammonia test strips

nitrite/nitrate test strips

Start Zyme

1

Exploring the Nitrogen Cycle

Name ______Date ______Period ______Score ______

  1. Predict what will happen to the bacteria over the next several days. Will the ammonia, nitrite, or nitrate levels increase? (They will start at ZERO)What effect will this have on the bacteria?
  1. Set up a 1-gallon aquarium with about ¾ of gallon of distilled or conditioned tap water at your workstation.
  2. Add enough aquarium pebbles to cover the bottom of the aquarium
  3. Pour one capful of Start Zyme into your tank. Start Zyme contains bacteria that convert ammonia.
  4. Following the directions on the bottles, measure the ammonia, nitrite, and nitrate levels in your aquarium. Record your results in data table.
  5. Repeat steps 5 on the next two days. Record your results and any noticeable changes to the water. If any water is added, record this as well

TEST / DAY 1 / Day 2 / Day 3 / Day 4 / Day 5
Ammonia
Nitrite
Nitrate
Water observations / DAY 1 / Day 2 / Day 3 / Day 4 / Day 5

Additional observations or changes in lab:

Graph your results:

Plant Tank Activity:

Materials:

1

Exploring the Nitrogen Cycle

Name ______Date ______Period ______Score ______

1 gallon aquarium

¾ gallon of distilled water

ammonia test strips

nitrite/nitrate test strips

foam plant quad

cotton ball

8 radish seeds

1

Exploring the Nitrogen Cycle

Name ______Date ______Period ______Score ______

  1. Predict what will happen to the seeds over the next several days. Will the ammonia, nitrite, or nitrate levels increase? (They will start at ZERO)What effect will this have on the seeds?
  1. Set up a 1-gallon aquarium with about ¾ of gallon of distilled or conditioned tap water at your workstation.
  2. Pull four small pieces of cotton from the cotton ball and place them at the bottom of each chamber of the foam quad. There should be just enough cotton to cover the hole.
  3. Place 2 radish seeds into each chamber of the quad.
  4. Place the quad into your aquarium so it floats. Push the quad into the water slighlt until the cotton in each chamber is wet.
  5. Following the directions on the bottles, measure the ammonia, nitrite, and nitrate levels in your aquarium. Record your results in data table.
  6. Repeat steps 6 on the next two days. Record your results and any noticeable changes to the water and seeds. If any water is added, record this as well

TEST / DAY 1 / Day 2 / Day 3 / Day 4 / Day 5
Ammonia
Nitrite
Nitrate
Water observations / DAY 1 / Day 2 / Day 3 / Day 4 / Day 5
Plant observations / DAY 1 / Day 2 / Day 3 / Day 4 / Day 5

Additional observations or changes in lab:

Graph your results:

Questions:

  1. What was missing in each of the tanks to prevent the nitrogen cycle from functioning? What arethe overall results in each experiment?
  1. What would happen to each tank without the nitrogen cycle, and why?
  1. Do fish create the nitrogen found in the ammonia they excrete? If not, where does this nitrogen come from?
  1. What was added to the system? If this were a closed system, how would it differ?
  1. What happened to pH levels as ammonia is converted to nitrate?
  1. Besides ammonia, what else needs to be present for the nitrification process to work?
  1. Humans have altered the influx of nitrogen at different stages of the nitrogen cycle. Pick one way in which this happens and explain what the long-term effects may be on the environment.
  1. Design an ideal tank that would sustain the nitrogen cycle and explain. (Hint: Make sure you utilize all parts of this lab.)

1