1. Nitrogen Cycle
The nitrogen cycle moves nitrogen from the air to the soil, into living things and back into the soil and back into the air.
Most organisms can’t use “Free” nitrogen (gas)
Nitrogen Fixation: this is the process that changes “free “ nitrogen into useable nitrogen
Most nitrogen fixation is done by bacteria (commonly found on plant roots)(legumes)
Once nitrogen has been “fixed” it can be used by organisms.

3. Nitrogen cycle Plants and animals absorb the nitrogen
Decomposers break down their waste and dead plant material and return the nitrogen back to the soil
Bacteria then absorbs the nitrogen and converts it back into “Free” nitrogen gas by the process of denitrification.
Nitrogen can cycle through plants and animals many times but eventually is returned to the air

4. Examples of the Nitrogen Cycle

5. What are the 2 most abundant gasses in Earth’s atmosphere?
Oxygen and carbon
Nitrogen and hydrogen
Oxygen and nitrogen
Oxygen and ozone
This is just a guess

6. I’ve fallen and I can’t get up
Which process in the Carbon Cycle, involves plants using carbon dioxide to make their own food?
Respiration
Condensation
Photosynthesis
Combustion
I’ve fallen and I can’t get up

7. Nitrogen fixation Denitrification Respiration Evaporation
Which process, in the Nitrogen Cycle, converts nitrogen from the air into a usable form for plants and animals?
Nitrogen fixation
Denitrification
Respiration
Evaporation
Please, please help me!