ABSTRACT
Bacteria are procaryotic organisms that, if photosynthetic, do not produce oxygen. Most bacteria are quite small, being rods, cocci or filaments that range from 0.5 to 1 μm in diameter. Since the resolution of the light microscope is of the order of 0.2 to 0.3 μm, it is easily understandable that no great progress was made in the cytology of bacteria before the introduction of the electron microscope and the development of allied methods of shadowing, thin-sectioning and staining.1-3
