By Vidya Rajan, Columnist, The Times Photosynthesis – a term that pretty much everyone understands – uses sunlight, carbon dioxide, water, and the light-harvesting green molecule, chlorophyll, to make sugars and release oxygen. Photosynthesis is carried out by free-living cyanobacteria, as well as plants and algae which contain chloroplasts, which are really just internal cyanobacteria, inside...