In which organelle does photosynthesis primarily take place?

Photosynthesis primarily takes place in chloroplasts, which are specialized organelles found in the cells of green plants and some algae. These organelles contain chlorophyll, the pigment that captures sunlight, allowing plants to convert light energy into chemical energy in the form of glucose. Chloroplasts are specifically adapted for this process, with structures like thylakoids where the light-dependent reactions occur and a stroma where the light-independent reactions (Calvin cycle) take place. This unique functionality distinguishes chloroplasts from other organelles, such as mitochondria, ribosomes, and the nucleus, which serve different essential roles in cellular function.