2.2 Prokaryotes and Eukaryotes
Notes
All cells have a cell membrane, cytoplasm, ribosomes, and DNA. They differ in how their DNA is stored.
- Prokaryotes (bacteria and archaea) have no nucleus and no membrane-bound organelles. Their DNA floats in a region called the nucleoid.
- Prokaryotes are small and simple; many have a cell wall, and some have flagella.
- Eukaryotes (protists, fungi, plants, animals) have a nucleus and membrane-bound organelles.
- Eukaryotic cells are usually much larger than prokaryotic cells.
Practice
A cell has ribosomes, a cell wall and DNA, but no nucleus. It is most likely:
No nucleus means it is a prokaryote, such as a bacterium.
Which structure is found in BOTH prokaryotic and eukaryotic cells?
All cells need ribosomes to make proteins.
Which group is made of eukaryotic cells?
Fungi, along with protists, plants and animals, are eukaryotes.
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