Name: ______________________________________
Date: ________________Period: __________
Biogeochemical cycles
I. CARBON CYCLE
(1)
(2)
(3)
Go to http://www.epa.gov/climatechange/kids/basics/today/carbon-dioxide.html Click
and complete scene 1.
Name 2 places on the earth we find carbon:
1. __________________________
2. ___________________________
Go to http://www.windows.ucar.edu/tour/link=/earth/Water/co2_cycle.html, read
about the carbon cycle and fill in the blanks below:
Plants pull carbon (in the form of carbon dioxide) from the atmosphere to make food,
through a process called ____________________.
Through food chains animals get ____________ from the plants and other animals they eat.
When plants and animals die and ____________, carbon goes back into the
ground.
Some carbon is buried deep in the ground and forms ________________________.
When humans burn fossil fuels, ________________ is released back into the atmosphere.
When humans and animals exhale, they release carbon back into the air by a process called
______________________________.
(4) Go to http://www.windows2universe.org/earth/Water/co2_cycle.html
How are oceans involved in the carbon cycle?
How is the temperature of the Earth partly controlled by carbon?
What role do rocks have within the carbon cycle?
How are humans altering the carbon cycle?
(5) Use this site to play a carbon game:
http://www.windows2universe.org/earth/climate/carbon_cycle.html Click to begin your
journey. Take notes on (1) where you begin the carbon cycle, (2) the stops that you make,
and (3) what you learn along the way.
Name: ______________________________________
Date: ________________Period: __________
Facts to find:
How much of the atmosphere is made of carbon dioxide?
By how much has CO2 increased in the atmosphere during the past 150 years?
The deep ocean accounts for more than ______% of the Earth’s carbon.
How much carbon does the surface ocean absorb from the atmosphere each year?
True or false. When plants die and decay, they bring carbon into soil.
True or False. Plants both absorb CO2 from the atmosphere and release it into the
atmosphere.
True or False. Phytoplankton are tiny plants and algae that float in the ocean and take up
carbon dioxide as they grow.
When carbon enters the deep ocean, how long does it stay there?
II. NITROGEN CYCLE
Go to the website:
http://www.windows.ucar.edu/tour/link=/earth/Life/nitrogen_cycle.html&edu=mid and
answer the questions below:
1. For what three things do plants and animals need nitrogen?
2.
What are 2 ways nitrogen becomes useable to plants, humans and animals?
3.
How do herbivores obtain the nitrogen they need?
4.
How is nitrogen returned to the atmosphere?
5.
What are two ways humans impact the nitrogen cycle:
1.
2.
6. What happens when there is an excess of nitrogen?
Like carbon, nitrogen must be recycled continuously. Go to the following websites to learn how
this happens:
https://www.classzone.com/...nitrogen/em05_pg20_nitrogen.swf
http://www.teachersdomain.org/asset/lsps07_int_nitrogen/
Name: ______________________________________
Date: ________________Period: __________
1. Where is most nitrogen in the biosphere located?
2. This nitrogen is not in a useable form. Plants and animals cannot simply absorb nitrogen
from the atmosphere. Therefore, it must be _____________________ , which means
________________________________.
3. There are two ways that nitrogen can be removed from the atmosphere:
a)
b)
4. What happens to nitrogen inside of a plant?
5. How does the nitrogen get to carnivores?
6. What happens to the nitrogen when organisms die?
7. What is the name of the process that returns nitrogen to the atmosphere?
8. Go to the following site and place a number next to
the steps involved in the nitrogen cycle:
http://ridge.icu.ac.jp/gen-ed/ecosystemjpgs/nitrogen-cycle.jpg
o nitrogen-fixation – (nitrogen in atmosphere converted
to ammonia by lightning or nitrogen-fixing bacteria)
_____
o nitrification (ammonia converted to nitrates by
nitrifying bacteria)_______
o assimilation (plants absorb nitrates, incorporate into
proteins. Nitrogen in now in the food chain) _____
o ammonification (dead plants/animals converted to
ammonia by ammonifying bacteria) _____
o denitrification (some nitrates are returned to atmosphere by denitrifying bacteria) _______
9. What type of organism do you notice is essential in nearly every stop of the nitrogen
cycle?
III. WATER CYCLE
1. http://education.jlab.org/reading/water_cycle.html
1. The ______________ evaporates _____________ from lakes and oceans. As the air
rises, it cools. The water vapor condenses into tiny droplets of _______________. The
Name: ______________________________________
Date: ________________Period: __________
droplets crowd together and form a __________. Wind blows the ______________
towards the land. The tiny droplets join together and fall as precipitation to the
____________. The water soaks into the ground and collects in ___________. The
___________ that never ends has started again!
2. Identify each number in the picture below
IV. PHOSPHOROUS CYCLE
Go to: http://filebox.vt.edu/users/chagedor/biol_4684/Cycles/Pcycle.html and answer these
questions based on the “soil based view” of the phosphorus cycle.
1. How does phosphorus initially enter the cycle?
2. What do plants do with it?
3. How do herbivores get it?
4. How do carnivores get it?
5. How do herbivores and carnivores return phosphorus to the cycle?
6. Why do living things need phosphorus?