Question 1
Which process removes carbon dioxide from the atmosphere?
- Combustion
- Photosynthesis
- Respiration
- Decomposition
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Answer: B – photosynthesis uses carbon dioxide to make glucose (1)
Question 2
Dead leaves fall to the ground and are broken down. Describe how the carbon in the leaves is returned to the atmosphere.
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- decomposers / bacteria and fungi break down the leaves (1)
- decomposers respire (1)
- releasing carbon dioxide (into the air) (1)
- allow CO₂
Question 3
Describe how carbon dioxide is removed from the atmosphere and how it is returned to the atmosphere in the carbon cycle.
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- plants / algae take in carbon dioxide (1)
- for photosynthesis (1)
- respiration (by plants, animals and decomposers) returns carbon dioxide (1)
- combustion of fuels / burning releases carbon dioxide (1)
- decomposition / decay releases carbon dioxide (1)
- Max 4