IGCSE Biology glossary
Prokaryote
Biology editorial review is supported by the named review panel. Reviewer participation may vary by guide. Checked against Cambridge IGCSE Biology 0610 (2026–2028); last reviewed August 2026.
Definition
An organism whose cells lack a true nucleus and membrane-bound organelles. The DNA lies free in the cytoplasm as a single circular chromosome. Bacteria are prokaryotes. They also have a cell wall, but it is not made of cellulose.
What to include in an exam answer
The key distinction from eukaryotes is 'no nucleus' or 'DNA not enclosed in a nuclear envelope'. Also state 'no membrane-bound organelles such as mitochondria or chloroplasts'.
Example in context
State two differences between a prokaryotic cell and a eukaryotic cell (2 marks): Prokaryotic cells have no true nucleus (DNA free in cytoplasm) and no membrane-bound organelles, while eukaryotic cells have a nucleus enclosed by a nuclear envelope and contain membrane-bound organelles.
Related syllabus topic
Characteristics & classification of living organisms