Cycles

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

• Water

• Atmosphere

• Sun

• Air

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

• respiration and photosynthesis

•  decomposition and respiration

In the carbon cycle, producers take in the gas __

• carbon dioxide

• oxygen

• nitrogen

• carbon monoxide

In what process is Carbon transformed into chemical energy?

• Photosynthesis

• Respiration

• Primary Production

• Secondary Production

What is happening at 1?

• respiration: releasing CO2

• decomposing CO2 in the soil

• photosynthesis: absorbing CO2

• turning CO2 from the atmosphere into organic molecules

What is the role of decomposers in an Ecosystem? 

• They recycle matter and nutrients to form fossil fuels

• They are burn and release as carbon dioxide

• Decomposers are responsible to turn oxygen into carbon dioxide

• They recycle energy back to the sun

Using fossil fuels is a safe for the environment. 

• True

• False

Organisms that need nitrogen to survive

• only plants

• only animals

• only bacteria

• all living organisms

Organisms that play a role in the nitrogen cycle

• only plants

• only animals

• only bacteria

• plants, animals, & bacteria

Plants and animals need nitrogen to make __________.

• Protein

• Carbohydrates

• Lipids

• Nucleic Acids