[youtube=http://www.youtube.com/watch?v=yKtUxLdBgJE]
For those interested (from textbookofbacteriology.net)
MAJOR NUTRITIONAL TYPES OF PROKARYOTES
| Nutritional Type | Energy Source | Carbon Source | Examples |
| Photoautotrophs | Light | CO2 | Cyanobacteria, some Purple and Green Bacteria |
| Photoheterotrophs | Light | Organic compounds | Some Purple and Green Bacteria |
| Chemoautotrophs or Lithotrophs (Lithoautotrophs) | Inorganic compounds, e.g. H2, NH3, NO2, H2S | CO2 | A few Bacteria and many Archaea |
| Chemoheterotrophs or Heterotrophs | Organic compounds | Organic compounds | Most Bacteria, some Archaea |