Test site: Mitochondria and chloroplasts are two kinds of energy converters in cells. Analysis: Organisms that can grow with carbon dioxide as the main carbon source in nature are collectively called autotrophs. They mainly include plants and some microorganisms. The raw materials of photosynthesis are carbon dioxide and water, and the products are organic matter and oxygen. The place is chloroplast, provided that there is light, chloroplast can convert light energy into chemical energy and store it in organic matter. So plants are autotrophs, and plants belong to autotrophs, because there are some in plant cells. D Comment: Autotrophic organisms play an important role in the transformation of natural substances.