本题目来源于试卷: IB ESS Unit 2: Ecosystems & Ecology，类别为 IB环境系统与社会
[单选题]
There is continuous cy ;c3h .nhfoa st7rrnwhvq0cbm:3; *d9clintvhc f1e+ )eg+g of carbon from the atmosphere to other carbon sinks.+g)v1feeh+ tc
Identify the main source of energy for the carbon cycle.
A. Heat
B. Sunlight
C. Chemical energy
D. Energy from respiration
参考答案: B
本题详细解析:
Energy from the sun (Option B) is used to form carbon compounds throughnxpor ( n/z-pv 2d 4hcdli*;7o the process of photosynthesis. Heat (Option A) is a form o*7;oi(pldpcvn d/n ho r4-2xzf energy that cannot be converted to chemical energy by living things.
Chemical energy (Option C) is held in the bonds of organic compounds which are produced by photosynthesis, or comes from hydrothermal vents deep in the oceans. Even though it is an energy source, it is not the main source of energy for the carbon cycle.
Energy stored in chemical bonds is released (Option D) during respiration which is used to power the cells processes.
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