Final Answer:
The set of reactions that use H₂O and produce O₂ is the light-dependent reactions. These reactions occur in the thylakoid membranes during photosynthesis, utilizing light energy to split water and release oxygen. The answer is light-dependent reactions.
Step-by-step explanation:
The set of reactions that use H₂O and produce O₂ is the light-dependent reactions of photosynthesis. These reactions occur in the thylakoid membranes of chloroplasts and are a crucial stage in the process of photosynthesis.
During the light-dependent reactions, light energy is absorbed by chlorophyll and other pigments, leading to the splitting of water molecules (H₂O) into oxygen (O₂), protons (H⁺), and electrons. This oxygen is then released as a byproduct into the atmosphere.
The energy derived from the light-dependent reactions is used to generate ATP and NADPH, which are subsequently utilized in the light-independent reactions (Calvin cycle) to produce carbohydrates from carbon dioxide.