The Nitrogen Cycle Homework Questions

tube.com / watch?v=leHy-Y_8nRs

tube.com / watch?v=b4rppYVkQFk (mistake at :57)

es.wordpress.c o m/2010/11/7-4-nitrogen-cycle.pdf

/air-climate-weather/biogeoch e mical-cycles/nitrogen-cycle/

Nitrogen (N) is an essential component of DNA, RNA, and proteins, the building blocks of life. All organisms require nitrogen to live and grow!!

Write the formula for:

a. Nitrogen gas

b. Ammonia

c. Ammonium

d. Nitrate

e. Nitrite

1. What happens during nitrogen fixation? (Include organisms involved, where they can be found and chemical conversions)

2. What happens during ammonification? (Include organisms involved, where they can be found and chemical conversions) Caution there is an error in the second video on this…check out the last link for accuracy.

3. What happens during nitrification? (Include organism involved, where they can be found and chemical conversions)

4. What is meant by nitrogen assimilation (uptake)?

5. What happens to the organic Nitrogen (DNA, RNA, proteins) in an organism when it dies or decomposes? (Include chemical conversions)

6. What happens during dentrification? (Include organisms involved, where they can be found and chemical conversions)

7. Describe several ways in which Humans have altered the nitrogen cycle. (To answer this you will need to do some research)

8. Create a diagram of the nitrogen cycle. (you CANNOT cut and paste one)

The Phosphorus Cycle Homework Questions

tube.com/watch?v=leHy-Y_8nRs

a nasinc.com/web c ontent/animations/content/phosphorouscycle.html

encelearn. o rg.nz/Contexts/Soil-Farming-an d -Science/Science-Ideas-and-Concepts/The-phosphorus-cycle

/air-climate-weather/biogeochemical-cycles/phosphorus-cycle/

Phosphate can be found in cell membranes, DNA, RNA, ATP , bone, teeth and exoskeletons and therefore is an essential nutrient for plants and animals.

Phosphorus DOES NOT EXIST as a gas, so it does not cycle in the atmosphere.

Usable forms for life

· Inorganic phosphate ion (PO43-) - autotrophs only

· Organic phosphate ion (PO43-) – autotrophs and heterotrophs

1. What is the lithosphere?

2. Where is Phosphorus most commonly found?

3. What happens to P during weathering?

4. What happens to P during leaching/runoff?

5. What happens to P during decomposition?

6. How long can a P molecule be trapped in a rock?

7. How long can a P molecule be trapped in a biological cycle?

8. What happens in lakes (Lake Champlain) when humans add too much phosphorus into the environment? (To answer this you will need to do some research)