本题目来源于试卷: Continuity and Change D.11 Stability & Change，类别为 IB生物学
[单选题]
There is continuous cycl6a. at,ksjl0 ning of carbon from the atmosphere to other carbon sink ry/ by ,x0o9edq-es3y2n3tlcs. Which is the main source of energ9byee2 lds3o nt0r-q ,y3/c yxy 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 (Choice B) is used to form carbon compounds through the process of photosynthesis. Heat (Choice A) is a form of energy that cannot be converted to chemical energy by living things. Chemical energy (Choice 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 (Choice D) during respiration forming ATP which is used to power the cells metabolic processes.
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