Bacteria:
* E. coli: A common bacterium found in the human gut, some strains are beneficial while others can cause illness.
* Staphylococcus aureus: A bacterium that can cause skin infections, food poisoning, and other illnesses.
* Streptococcus pneumoniae: A bacterium that can cause pneumonia, meningitis, and ear infections.
* Salmonella: A bacterium that can cause food poisoning and other illnesses.
* Cyanobacteria: A group of bacteria that can produce oxygen through photosynthesis.
Archaea:
* Methanogens: Archaea that produce methane gas. They are often found in anaerobic environments, such as swamps and the digestive systems of animals.
* Halophiles: Archaea that thrive in extremely salty environments, such as salt lakes and salt flats.
* Thermophiles: Archaea that can survive in extremely hot environments, such as hot springs and hydrothermal vents.
It's important to note that the classification of prokaryotic organisms is constantly being refined. New species are discovered regularly, and our understanding of their relationships is evolving.
