Stroma (pl. stromata) 1. The colorless ground matter between the grana lamellae in a CHLOROPLAST. It is the site of the dark (light-independent) reactions of photosynthesis.

• 基质：是叶绿体内的叶绿体基粒片层结构之间的无色透明物质。为光合作用暗反应（依赖光）的发生场所。