Which part of the chloroplast is the primary site where the light-dependent reactions of photosynthesis occur?

• A. Outer membrane
• B. Intermembrane space
• C. Thylakoid membrane
• D. Stroma

Answer: (C)

Verified step by step guidance

1. Understand the structure of the chloroplast: The chloroplast is an organelle found in plant cells and is responsible for photosynthesis. It has several key components, including the outer membrane, inner membrane, intermembrane space, stroma, and thylakoid membrane.
2. Learn about the light-dependent reactions: These reactions are the first stage of photosynthesis and require light energy to produce ATP and NADPH. They involve the absorption of light by chlorophyll and other pigments, which are embedded in the thylakoid membrane.
3. Identify the role of the thylakoid membrane: The thylakoid membrane contains protein complexes such as Photosystem I, Photosystem II, the cytochrome b6f complex, and ATP synthase. These complexes are essential for capturing light energy and converting it into chemical energy.
4. Compare the options provided: The outer membrane and intermembrane space are structural components of the chloroplast but do not participate directly in the light-dependent reactions. The stroma is the site of the light-independent reactions (Calvin cycle), not the light-dependent reactions.
5. Conclude that the thylakoid membrane is the correct answer: Based on the structure and function of the chloroplast, the thylakoid membrane is the primary site where the light-dependent reactions of photosynthesis occur.