In the first reaction, energy is used to split water molecules into hydrogen and oxygen. The hydrogen is needed for the second stage of reactions and the oxygen is released by the plant as a waste product. In the reactions of the second stage, the hydrogen is combined with carbon dioxide to make glucose.
Answer:In the first reaction, energy is used to split water molecules into hydrogen and oxygen.
Explanation: The hydrogen is needed for the second stage of reactions and the oxygen is released by the plant as a waste product. In the reactions of the second stage, the hydrogen is combined with carbon dioxide to make glucose.