Inheritance & EvolutionKey Facts

The Three Domain System

Part of Classification — GCSE Biology

This key facts covers The Three Domain System within Classification for GCSE Biology. Classification systems, taxonomy, and evolutionary relationships It is section 2 of 11 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.

Topic position

Section 2 of 11

Practice

25 questions

Recall

20 flashcards

The Three Domain System

Carl Woese proposed classifying life into three domains based on DNA:

ARCHAEA
Ancient bacteria-like organisms
Extreme environments

BACTERIA
True bacteria
Prokaryotes

EUKARYOTA
All other life
Animals, plants, fungi, protists

Keep building this topic

Read this section alongside the surrounding pages in Classification. That gives you the full topic sequence instead of a single isolated revision point.

The Linnaean Classification System Binomial Naming System How It Works: Classification and Why It Changes Key Definitions

Practice Questions for Classification

What is the highest level in the Linnaean classification system?

A. Species
B. Kingdom
C. Phylum
D. Class

1 markfoundation

What is the purpose of classifying living things based on their DNA and genome characteristics?

2 marksstandard

Quick Recall Flashcards

How do you correctly write a binomial (scientific) name?

Genus name first with CAPITAL letter, species name second in lower case — e.g. Homo sapiens. Both words are italicised when typed or underlined when handwritten. Example: Felis catus (domestic cat), Panthera leo (lion).

What is biological classification?

The process of sorting organisms into groups based on shared characteristics and evolutionary relationships. Classification helps scientists name, study, and communicate about the huge variety of life on Earth.

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The Linnaean Classification System

Binomial Naming System