Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: The cardiovascular system moves nutrients and other substances throughout the body. Answer: cardiovascular system

A: Which human body system system moves nutrients and other substances throughout the body?
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Q: Passage: Transcription takes place in three steps: initiation, elongation, and termination. The steps are illustrated in Figure below . Answer: transcription

A: Initiation, elongation, and termination are the three steps of what?
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Q: Passage: The light reactions occur in the first stage of photosynthesis. This stage takes place in the thylakoid membranes of the chloroplast. In the light reactions, energy from sunlight is absorbed by chlorophyll. This energy is temporarily transferred to two molecules: ATP and NADPH. These molecules are used to store the energy for the second stage of photosynthesis. The light reactions use water and produce oxygen. Answer: first stage

A:
Light reactions occur during which stage of photosynthesis?
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