Carbon and Nitrogen Cycle

When humans burn fossil fuels, most of the carbon quickly enters the ____________ as carbon dioxide.

Which one of these does not add CO2 to the atmosphere?

Combustion is another word for _______________.

What does not produce carbon dioxide?

How do living organisms return carbon to the atmosphere in the carbon cycle?

(Check all that apply) Why is the increase of Greenhouse gasses a big issue?

Why is the carbon cycle important?

Carbon is used by plants during which process?

What molecules do plants produce using nitrogen?

In which form do animals gain nitrogen?

The diagram (click to enlarge) shows part of the nitrogen cycle.

Which of the numbered stages involve bacteria?

The diagram below shows part of the nitrogen cycle.

Which stage is decomposition? (click any that apply)

The diagram shows part of the nitrogen cycle.

Which stage is nitrification?

Which kind of organisms are decomposers?