What is the primary function of thylakoid membranes in photosynthesis?

The primary function of thylakoid membranes in photosynthesis is to contain chlorophyll and facilitate light-dependent reactions. Thylakoids are membrane-bound structures within the chloroplasts where the light-dependent reactions of photosynthesis occur. These reactions take place in the thylakoid membranes, which house chlorophyll and other pigments that capture light energy. This energy is then used to drive the synthesis of ATP and NADPH, which are crucial for the subsequent light-independent reactions (Calvin cycle).

The thylakoid membranes also create a proton gradient by allowing protons to flow into the thylakoid lumen during the electron transport chain, ultimately leading to the production of ATP through ATP synthase. Therefore, the correct answer highlights the essential role of thylakoid membranes in enabling the absorption of light energy and the conversion into chemical energy, which is vital for the process of photosynthesis. Other options do not accurately reflect the specific functions associated with thylakoid membranes.