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 nb 0e/,*yqlf+ndqdk; cycling of carbon from the atmosphereio+*5t /hd3;f uvzt frzw1/ dj to other carbon sinks. Which is the main source of energy for thdr ;/1h5fdvt jf+/ z3it*zw uoe 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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