Explain how the five kingdoms used to classify living organisms differ from one another. In your answer, refer to at least three of the five kingdoms.
Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).
Model answer (4 marks)
Animals (Animalia) are multicellular, lack cell walls, and are heterotrophic.
Plants (Plantae) are multicellular, have cellulose cell walls, and are autotrophic.
Fungi are mostly multicellular, have chitin cell walls, and feed by decomposition (saprophytic) – they cannot photosynthesise.
Prokaryotes (Monera) are unicellular and lack a membrane‑bound nucleus.
Protozoa (Protoctista) are mostly unicellular, have a nucleus, and can be heterotrophic or autotrophic.
Plants (Plantae) are multicellular, have cellulose cell walls, and are autotrophic.
Fungi are mostly multicellular, have chitin cell walls, and feed by decomposition (saprophytic) – they cannot photosynthesise.
Prokaryotes (Monera) are unicellular and lack a membrane‑bound nucleus.
Protozoa (Protoctista) are mostly unicellular, have a nucleus, and can be heterotrophic or autotrophic.
Examiner tips
- Use the key terms: multicellular, cell wall, autotrophic/heterotrophic, nucleus, chitin vs cellulose.
- Show clear comparisons between at least three kingdoms.
- Keep sentences short and factual to fit the 4‑mark limit.
Common mistakes
- Mixing up cell wall material (cellulose vs chitin).
- Forgetting that fungi are mostly multicellular.
- Using the wrong term for prokaryotes (e.g., calling them eukaryotes).
Mark scheme (4 marks)
- Animals (Animalia) are multicellular and cannot photosynthesise / do not have cell walls / are heterotrophic
- Plants (Plantae) are multicellular, have cell walls made of cellulose, and can photosynthesise / are autotrophic
- Fungi are multicellular (mostly), have cell walls made of chitin (not cellulose), and feed by decomposition / are saprophytic / cannot photosynthesise
- Prokaryotes (Prokaryotae/Monera) have no membrane-bound nucleus / are unicellular; OR Protoctists are mostly unicellular and have a membrane-bound nucleus (eukaryotic)
Key terms in this question
Related
- All WJEC GCSE Biology (Wales) revision notes →
- How to answer a "Explain" question →
- Decode the mark scheme abbreviations →