Summary
Highlights
Earth hosts two primary cell types: prokaryotic and eukaryotic. Prokaryotic cells are the simplest and most ancient, existing for billions of years before the emergence of eukaryotic cells.
Prokaryotic cells are smaller and possess a simpler structure, which aids in rapid reproduction. They lack a nucleus (as 'prokaryote' means 'before nucleus') and membrane-bound organelles. Their DNA is located in the nucleoid region, and they have a cell wall and often flagella for movement.
Eukaryotic cells, meaning 'true nucleus,' contain a membrane-bound nucleus and other membrane-bound organelles. They are generally larger and more complex than prokaryotic cells.
Both prokaryotic and eukaryotic cells share several commonalities: they both have DNA as their genetic material, ribosomes, cytoplasm, and a plasma membrane.
Key differences include prokaryotes being older, smaller, and simpler, lacking a nucleus and membrane-bound organelles, and being single-celled with circular DNA. Eukaryotes evolved later, are larger and more complex, possess a nucleus and organelles, can be single or multicellular, and have linear DNA.