Carbon Cycle Quiz for 8th Graders

Which process removes carbon dioxide from the atmosphere and converts it into organic compounds?

• Respiration

• Photosynthesis

• Combustion

• Decomposition

What is the main source of energy for photosynthesis?

• Water

• Carbon dioxide

• Sunlight

• Oxygen

Which of the following is NOT a way that carbon dioxide returns to the atmosphere?

• Respiration

• Combustion

• Decomposition

• Condensation

In the carbon cycle, what do we call the process where living things breakdown food for energy?

• Photosynthesis

• Respiration

• Combustion

• Feeding

Which organisms play a crucial role in decomposition in the carbon cycle?

• Plants

• Animals

• Bacteria and fungi

• Fish

What happens to the carbon in dead plants and animals?

• It disappears

• It turns into oxygen

• It is decomposed and released as carbon dioxide

• It stays locked in the organism forever

How does burning fossil fuels affect the carbon cycle?

• It removes carbon dioxide from the atmosphere

• It has no effect on the carbon cycle

• It releases stored carbon into the atmosphere as carbon dioxide

• It converts carbon dioxide into oxygen

Which of the following is an example of combustion in the carbon cycle?

• A tree growing taller

• A fire burning wood

• A cow eating grass

• A leaf falling from a tree

What role does feeding play in the carbon cycle?

• It removes carbon dioxide from the atmosphere

• It transfers carbon from one organism to another

• It converts carbon dioxide into oxygen

• It has no role in the carbon cycle

Which process in the carbon cycle is most similar to combustion in terms of its effect on atmospheric carbon dioxide?

• Photosynthesis

• Feeding

• Respiration

• Decomposition