Carbon cycle

What does NOT produce carbon dioxide?

• Photosynthesis
• Burning Fossil Fuels
• Animal respiration
• Plants decaying

Combustion is another word for __________.

• Transportation
• Respiration
• Fossil Fuels
• Burning

TRUE or FALSE?
All of the carbon in existence is continually recycled in the carbon cycle.

• True
• False

Organisms that do not decompose can be buried and become what?

• water
• nutrients
• air
• fossil fuels

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
• Death

What process occurs when coal (fossil fuel) is used for energy?

• Decomposition
• Combustion
• Pressurization 
• Respiration 

The diagram shows the flow of organic molecules through an ecosystem. What two processes are identified by the labels X and Y?

• X : Respiration
  Y : Predation
• X : Adaptation
  Y : Decomposition
• X : Fermentation
  Y : Nitrogen Fixation
• X : Decomposition
  Y : Respiration

The average temperature of the surface of Earth has increased approximately 1°C in the past century. Which reason best explains this increase in temperature?

• lower levels of ozone in the atmosphere
• lower levels of nitrogen in the atmosphere
• higher levels of carbon dioxide and other greenhouse gases in the atmosphere
• higher levels of oxygen in the atmosphere

How does carbon become locked inside the earth?

• Tree roots expel carbon into the soil as they grow.

• Humans use machines to pump carbon dioxide into large underground rocks.

• Rocks become richer in carbon as time goes by.

• The carbon-rich bodies of plants and animals decay into the earth after they die.