Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.

Q: Question: What occurs when there is a sudden discharge of static electricity between a cloud and the ground? Answer: lightning

A: Lightning occurs when there is a sudden discharge of static electricity between a cloud and the ground.
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Q: Question: What changes the chemical composition of a substance and can only occur through a chemical reaction? Answer: chemical changes

A: Pure substances, such as compounds, can be separated through chemical changes. Chemical changes change the chemical composition of a substance and can only occur through a chemical reaction.
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Q: Question: What is the first step of the calvin cycle called? Answer: carbon fixation

A:
The Calvin cycle has three major steps: carbon fixation, reduction, and regeneration. All three steps take place in the stroma of a chloroplast.
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