Three-domain system
What Three-domain system means in Combined Science GCSE, as defined for AQA.
Definitions of Three-domain system
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Reference: AQA
A system in which bacteria are placed in their own domain, distinct from Archaea and Eukaryota based on biochemical differences.
A classification model developed by Carl Woese that places organisms into three broad groups above kingdom level.
Topics that use Three-domain system
- Classification of living organisms (AQA GCSE)
Related terms
- Archaea
- Binomial nomenclature
- Carl Woese and scientific models
- Changing scientific models
- Comparing cell types
- Eukaryota
- eukaryotic cells
- Evidence for classification
Using Three-domain system in the exam
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