Geochemical Cycle

Humans burn fossil fuels and wood, releasing carbon dioxide into the atmosphere. This carbon dioxide is then absorbed by trees for photosynthesis. These processes are contributory to which chemical cycle?

• The carbon cycle

• The water cycle

• The nitrogen cycle

• The phosphorous cycle

In the carbon cycle, animals can release carbon back into the cycle through __________ or through __________.

• burning . . . photosynthesis

• fixation . . . decomposition

• decomposition . . . photosynthesis

• respiration . . . decomposition

• respiration . . . photosynthesis

Which of the following is an example of human impact on the carbon cycle?

• The increased production of methane gases from cattle farms

• The burning of fossil fuels

• The cutting down of trees for lumber

• Driving automobiles

• All of the above

If a forest fire occurs, what will happen to the carbon in the forest?

• It will go into the soil

• It will go into the atmosphere

• It will runoff into nearby streams and rivers

• It will be destroyed

Where does all the carbon in organisms (living things) originate from?

• Earth's atmosphere

• Rocks

• Water

• Soil

How do organisms (living things) move carbon through the carbon cycle?

• Respiration only

• Decomposition only

• Photosynthesis, respiration, and decomposition

• Decomposition and sedimentation

• Respiration, decomposition, sedimentation, and photosynthesis

By what method is the majority of carbon moved from the lithosphere (upper part of Earth's crust) to the atmosphere?

• Weathering

• Deposition

• The burning of fossil fuels

• Respiration

What kind of organism takes out the most carbon from the atmosphere?

• Plants

• Bacteria

• Animals

• Humans

What does NOT produce carbon dioxide?

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

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

• True
• False