CIE iGCSE Co-Ordinated Science B19.2 Conservation Exam Style Questions Paper 1
▶️ Answer/Explanation
Transpiration is the evaporation and movement of water through plants and out via the stomata — it is part of the water cycle, not the carbon cycle.
Combustion, fossilisation, and photosynthesis all involve the movement of carbon between the atmosphere, living organisms, and the Earth, so they are all parts of the carbon cycle.
✅ Answer: (C)
Combustion, fossilisation, and photosynthesis all involve the movement of carbon between the atmosphere, living organisms, and the Earth, so they are all parts of the carbon cycle.
✅ Answer: (C)
▶️ Answer/Explanation
Photosynthesis must show carbon dioxide moving from the air into plants, while respiration moves carbon dioxide from both plants and animals back into the air.
Feeding must show carbon moving from plants to animals only, in one direction.
Diagram A shows these three arrows going in the correct directions between air, plants and animals.
✅ Answer: (A)
Feeding must show carbon moving from plants to animals only, in one direction.
Diagram A shows these three arrows going in the correct directions between air, plants and animals.
✅ Answer: (A)
▶️ Answer/Explanation
Removing trees reduces interception of rainfall and water uptake by roots, increasing surface run-off and the risk of flooding.
Fewer trees means less carbon dioxide is removed from the atmosphere by photosynthesis, so the amount of atmospheric carbon dioxide increases.
✅ Answer: (D)
Fewer trees means less carbon dioxide is removed from the atmosphere by photosynthesis, so the amount of atmospheric carbon dioxide increases.
✅ Answer: (D)
▶️ Answer/Explanation
The graph shows atmospheric CO₂ steadily increasing over the years.
Photosynthesis removes CO₂ from the atmosphere: \( 6CO_2 + 6H_2O \xrightarrow{\text{light}} C_6H_{12}O_6 + 6O_2 \).
A reduction in photosynthesis (e.g. through deforestation) means less CO₂ is removed, explaining the rising trend.
✅ Answer: (C)
Photosynthesis removes CO₂ from the atmosphere: \( 6CO_2 + 6H_2O \xrightarrow{\text{light}} C_6H_{12}O_6 + 6O_2 \).
A reduction in photosynthesis (e.g. through deforestation) means less CO₂ is removed, explaining the rising trend.
✅ Answer: (C)
▶️ Answer/Explanation
Burning forests releases stored carbon as carbon dioxide directly into the atmosphere.
It also removes trees that would otherwise absorb CO₂ during photosynthesis, worsening the effect.
Planting more crops or using fewer fossil fuels would instead reduce, not increase, atmospheric CO₂.
✅ Answer: (A)
It also removes trees that would otherwise absorb CO₂ during photosynthesis, worsening the effect.
Planting more crops or using fewer fossil fuels would instead reduce, not increase, atmospheric CO₂.
✅ Answer: (A)