There are two types of cells, prokaryotic and eukaryotic. The first prokaryotic cell fossil records date back to about 3.5 billion years ago, while the first cells resembling eukaryotes appear about two billion years later. Although the types of cell share some similarities, compartmentalization is not a shared characteristic.


1. Describe the endosymbiotic theory.
2. Explain the relationship between the functions of endosymbiotic organelles and their free-living ancestral counterparts. Provide evidence that supports the endosymbiotic theory.