The Chloroplast is a structure found in plant cells that provides the necessary structures for photosynthesis. It is filled with the chemical chlorophyll which is a vital compound to facilitate photosynthesis. Because of the fact that chlorophyll is green, it has a green color. It has an inner and outer membrane and has several different kinds of molecules within it that allow the process to take place. See the photosynthesis page under the biochemistry heading for more information.