Prokaryotes and Endosymbiosis

Prokaryotes are a single celled organisms that do not have a membrane bound nucleus or mitochondria. Prokaryotes are broken into two groups archaea and bacteria. Archaea is a group of single celled microorganism. Archaea are still prokaryotes with no cell nucleus or membrane bound organelles. Bacteria is a large domain of prokaryotic microorganisms and tend to be a few micrometers in length. Bacteria vary in a number of shapes, they have been seen in spheres, rods and spirals.
One thing that makes prokaryotes so special is the way we think they were evolved 3.9 billion years ago. We think that Prokaryotes were evolved by endosymbiosis. Endosymbiosis is a process where one organism “swallows” another. Now after endosymbiosis there is one organism inside of the other and they are both thriving off of each other. This creates the start what might be the beginning of a prokaryote.

References:
The Evolution of the Cell. (2014). Retrieved September 22, 2014, from Learn.Genetics.Utah website: http://learn.genetics.utah.edu/content/cells/organelles/
Evidence for an early prokaryotic endosymbiosis [journal abstract]. (2014). Retrieved September 24, 2014, from Nature International Weekly Journal of Science website: http://www.nature.com/nature/journal/v460/n7258/full/nature08183.html