carbon cycle

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

• Water

• Atmosphere

• Sun

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

• respiration and photosynthesis

• decomposition and respiration

In the carbon cycle, trees and plants take in the gas __

• carbon dioxide

• oxygen

• nitrogen

All of the carbon in existence is continually recycled in the carbon cycle

• True

• False

Combustion is another word for __________.

• Transportation

• Respiration

• Fossil Fuels

• Burning

Carbon can be found in...

• The atmosphere

• Soil

• Fossil fuels

• All of the above

Which of the following removes carbon from the atmosphere?

• Combustion

• Respiration

• Photosynthesis

Respiration is the process by which animals take in _____ and release _____.

• oxygen, carbon dioxide

• water, sunlight

How is the burning of fossil fuels related to global warming?

• Photosynthesis

• Fuels are hot

• Greenhouse effect

Which of the following is an example of a decomposer?

• Owl

• Fish

• Tree

• Mushroom