Control Mechanisms in Developmental Processes

The metabolic activity of the plastid which is of greatest significance to the organism as a whole is photosynthesis, including the capture of light energy, its conversion to electrochemical energy, and the storage of this energy in carbon bonds. Thus, the chloroplast does photochemistry, electron transport, and carbon metabolism in the course of carrying out its photosynthetic activities. Precisely what the plastid does strictly for its own development and maintenance is more difficult to define. This discussion will deal primarily with chemical changes during the development of plastids in leaves of higher plants.