Eukaryotes and prokaryotes
Bacteria are amongst the simplest of organisms – they are made of single cells. Their cell structure is simpler than the cells of animals, plants and fungi.
- Cells of bacteria are called A simple cell that does not have a nucleus – the DNA is free in the cytoplasm. .
- Cells of animals, plants and fungi are called A type of cell that has a nucleus..
Comparing cell types
| Eukaryotic cell | Prokaryotic cell | |
| Size | Most are 5 μm – 100 μm | Most are 0.2 μm – 2.0 μm |
| Outer layers of cell | Cell membrane - surrounded by cell wall in plants and fungi | Cell membrane - surrounded by cell wall |
| Cell contents | Cytoplasm, cell organelles include mitochondria, chloroplasts in plants and ribosomes | Cytoplasm, ribosomes, no mitochondria or chloroplasts |
| Genetic material | DNA in a nucleus - plasmids are found in a few simple eukaryotic organisms | DNA is a single molecule, found free in the cytoplasm - additional DNA is found on one or more rings called plasmids |
| Type of cell division | Mitosis | Binary fission |
| Size | |
|---|---|
| Eukaryotic cell | Most are 5 μm – 100 μm |
| Prokaryotic cell | Most are 0.2 μm – 2.0 μm |
| Outer layers of cell | |
|---|---|
| Eukaryotic cell | Cell membrane - surrounded by cell wall in plants and fungi |
| Prokaryotic cell | Cell membrane - surrounded by cell wall |
| Cell contents | |
|---|---|
| Eukaryotic cell | Cytoplasm, cell organelles include mitochondria, chloroplasts in plants and ribosomes |
| Prokaryotic cell | Cytoplasm, ribosomes, no mitochondria or chloroplasts |
| Genetic material | |
|---|---|
| Eukaryotic cell | DNA in a nucleus - plasmids are found in a few simple eukaryotic organisms |
| Prokaryotic cell | DNA is a single molecule, found free in the cytoplasm - additional DNA is found on one or more rings called plasmids |
| Type of cell division | |
|---|---|
| Eukaryotic cell | Mitosis |
| Prokaryotic cell | Binary fission |
A group of organisms called Microorganisms which are similar in size and structure to bacteria but are genetically different. are also prokaryotic.