The Calvin cycle takes place in the chloroplasts of plant cells, specifically in the stroma, which is the fluid-filled space surrounding the thylakoids. This cycle is essential for photosynthesis, as it uses carbon dioxide and the energy derived from ATP and NADPH produced in the light-dependent reactions to synthesize glucose and other carbohydrates.
The stroma provides the necessary enzymes and substrates required for the Calvin cycle to occur. During this cycle, carbon dioxide is fixed into an organic molecule, eventually leading to the production of glucose. This process is crucial for converting inorganic carbon into a form that can be utilized by living organisms, thus sustaining life on Earth.