Bacteria and archaea

They're everywhere. They number in the millions of trillions of trillions. They live on every surface, in every environment, and even in your gut. That's right...I'm talking about prokaryotes! Learn more about bacteria and archaea.
See how you score on these 8 practice questions

Learn about the structure, reproduction, and genetics of bacteria (as well as archaea, a lesser-known but also important group of prokaryotes)!

Prokaryotes may not have complex, multicellular bodies, but they are still remarkably diverse! Learn about the metabolism, ecology, and major groups of bacteria and archaea.