Where are pigments arranged and what is a broader term for this arrangement?

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Pigments that absorb light are arranged in the thylakoid membranes of chloroplasts into light-harvesting antenna complexes that capture photons and funnel energy to a reaction center embedded in a photosystem. This organized assembly—the antenna pigments plus the reaction center forming a functional unit—is described by the broader term photosystems. The chloroplast stroma is the fluid inside where the Calvin cycle occurs, not the site of these pigment arrangements; mitochondrial inner membrane and respiratory complexes belong to cellular respiration, not photosynthesis. The thylakoid lumen is the internal space, not where the pigment systems are organized, and while light-harvesting complexes describe part of the structure, photosystems are the broader functional unit that encompasses the entire pigment–protein complex involved in primary light capture and charge separation.