This is the simpler of the two types of carbon-based cells known today, and it was the first one to evolve. In the prokaryotic cell, a cell wall encloses a liquid called cytoplasm within which is a single strand of DNA attached at one point to the plasma membrane. There is very little internal organization within the cell. Prokaryotes multiply by simple cell division, forming clones or exact copies of themselves. Since the offspring shares the exact same genetic code as the parent, their evolution is very slow.
Eukaryotic cells are much larger and more advanced.
These cells need oxygen to survive and they most likely evolved and lived near oxygen-producing stromatolites at first. Most importantly, eukaryotes reproduce sexually. Genetic material is mixed between two parents, and while the offspring resembles the parents in major features, minor genetic variations can yield subtle differences. The new characteristics sometimes help eukaryotic organisms to adapt to new environments. Life on Earth is based on the carbon atom, which is bonded to oxygen, hydrogen, nitrogen and other elements.