Light reaction during photosynthesis takes place in

Options

A. Outer surface of chloroplast envelope
B. Stroma
C. Thylakoid membrane
D. Inner surface of chloroplast envelope.

Answer

**Step-by-Step Solution:**

1. **Understanding Photosynthesis**: Photosynthesis is the process by which plants convert light energy into chemical energy to produce their own food. It consists of two main phases: light reactions and dark reactions.

2. **Identifying the Light Reaction**: The light reaction is the first phase of photosynthesis. It involves the conversion of light energy into chemical energy, resulting in the formation of ATP (adenosine triphosphate) and NADPH (nicotinamide adenine dinucleotide phosphate).

3. **Location of Light Reactions**: The light reactions specifically take place in the thylakoid membranes of the chloroplasts. This is where the light energy is captured and converted.

4. **Role of Thylakoid Membranes**: The thylakoid membranes contain chlorophyll and other pigments that absorb light energy. This energy is then used to facilitate processes such as photolysis of water, which produces oxygen.

5. **Exclusion of Other Options**:
- The outer surface of the chloroplast does not participate in the light reactions.
- The stroma is where the dark reactions occur, not the light reactions.
- The inner surface of the chloroplast is not a recognized site for light reactions.

6. **Conclusion**: Therefore, the correct answer to the question is that the light reactions during photosynthesis take place in the **thylakoid membrane** of the chloroplast.

**Final Answer**: The light reaction during photosynthesis takes place in the thylakoid membrane.

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