Prokaryotic character of chloroplasts and mitochondria — the present knowledge

When reconstructing the process of evolution we do not depend only on paleontological data. Due to the progress in molecular biology, it is possible to obtain more reliable information by the analysis of essential macromoleeules. The most important information comes from studies of the genes and their products that are universally distributed, functionally equivalent and conservative and that can be thus considered as reliable phylogenetic markers. The organization of chloroplast and mitochondrial genomes, and the comparative analysis of highly conservative macromolecules in particular (e.g. primary and secondary structure of rRNA and tRNA) yield a basis substantiating the prokaryotic origin of semiautonomous organelles of eukaryotic cells.