The Calvin Cycle of photosynthesis occurs in the stroma of chloroplasts in plant cells. The stroma is the fluid-filled space surrounding the thylakoid membranes where the light-dependent reactions of photosynthesis take place.
During the Calvin Cycle, carbon dioxide is fixed into organic molecules, ultimately producing glucose. This process does not require light directly but relies on the energy carriers (ATP and NADPH) generated during the light-dependent reactions. The stroma provides the necessary enzymes and other components for the cycle to occur, making it a crucial site for converting solar energy into chemical energy stored in carbohydrates.