What are two important differences between prokaryotic and eukaryotic cells?

The difference between the structure of prokaryotes and eukaryotes is so great that it is considered the most important difference among groups of organisms. Eukaryotic cells contain membrane-bound organelles such as the nucleus, while prokaryotic cells do. Differences in the cellular structure of prokaryotes and eukaryotes include the presence of mitochondria and chloroplasts, the cell wall, and the structure of chromosomal DNA. Prokaryotes were the only life on Earth for millions of years before more complex eukaryotic cells emerged during evolution.