2. Types of Cells
• Cells can be divided into two major groups based
on their major characteristics:
• Prokaryotic
• Eukaryotic
3. Prokaryotic Cells
• Occur in bacteria
• Much smaller than eukaryotic cells
• Thought to appear first on Earth
4.
5. Prokaryotic Cells
Key Points
• Their DNA is not enclosed within a membrane and it is
one circular chromosome
• They lack membrane bound organelles.
• Their cell wall is made up of a unique compound called
peptidogylcan (different to eukaryotes)
• They usually divide by binary fission, a simple form of
cell division
• They are characteristically small in size, usually 1- 10
micrometres.
6. Eukaryotic Cells
• Occur in organisms such as algae, protozoa,
fungi, plants and animals.
• Contain a nucleus
• Contain organelles
7.
8. Prokaryotic vs. Eukaryotic
Prokaryotic cells Eukaryotic cells
DNA in a ring form without
protein
DNA with proteins as
chromosomes/chromatin
DNA free in the cytoplasm DNA enclosed within a
nucleus
No mitochondria Mitochondria present
Contain ribosomes Contain ribosomes
No organelles Organelles
Size smaller than 10
micrometres
Size larger than 10
micrometres
