Explain why the binomial system of nomenclature is used by scientists worldwide when classifying organisms, rather than using common names.

OCR A-Level Biology A (H420) — 4.3 Classification and evolution · Explain · 4 marks · View as Markdown

Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).

Model answer (4 marks)

Common names vary between languages or regions, causing confusion.
The binomial system gives each species a unique, universally agreed name.
The genus part of the name shows the organism’s closest relatives, indicating evolutionary relationships.
Because Latin/Greek is a dead language, the meaning of the names does not change, ensuring stability.

Examiner tips

Use the word ‘unique’ and ‘universally agreed’ to hit the key point about standardisation.
Mention the genus revealing evolutionary relationships to show depth of explanation.
Show that Latin/Greek is a dead language to justify stability.
Keep each point concise – 4 points, 1 sentence each.

Common mistakes

Using only common names or not explaining why they are problematic.
Failing to mention the genus as a clue to evolutionary relationships.
Confusing the binomial system with a single scientific name or ignoring the Latin/Greek aspect.

Mark scheme (4 marks)

Common names vary between languages or regions, causing confusion
The binomial system provides a unique, universally agreed name for each species
The genus name indicates the organism's closest relatives / membership of a genus, revealing evolutionary relationships
Latin / Greek is a dead language so the meaning of names does not change over time, ensuring stability

Key terms in this question

binomial system · nomenclature · classifying