Answer :
Final answer:
During the light-dependent reactions of photosynthesis, water molecules are split through a process called photolysis. This reaction occurs in the thylakoid membranes and produces oxygen and energy carriers like ATP and NADPH. Other processes mentioned occur in the Calvin Cycle, which is separate from the light-dependent stage.
Explanation:
Light-Dependent Reactions of Photosynthesis
The light-dependent reactions are the first stage of photosynthesis, occurring in the thylakoid membranes of chloroplasts. One of the key processes that take place during these reactions is the splitting of water molecules, a process known as photolysis. This occurs when light energy is absorbed by chlorophyll, exciting electrons that ultimately lead to the production of ATP and NADPH.
During photolysis, water molecules are broken down into oxygen gas, protons, and electrons. The equation for this reaction can be simplified as follows:
- 2 H2O → 4 H+ + 4 e- + O2
The other options listed in your question, such as carbon fixation, occur in the light-independent reactions (Calvin Cycle), which follow the light-dependent reactions. In the Calvin Cycle, ribulose bisphosphate (RuBP) is regenerated and phosphoglycerate (PGA) is reduced, but these processes do not happen during the light-dependent stage.
Answer
Therefore, the correct answer to your question is: Water molecules are split.
Learn more about Light-Dependent Reactions here:
https://brainly.com/question/11240542