Viruses are considered non-living. Describe four features of viruses that distinguish them from living organisms such as bacteria.

Pearson Edexcel International GCSE Biology (4BI1) — 1.2 Variety of living organisms · Describe · 4 marks · View as Markdown

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

Model answer (4 marks)

Viruses have no cells – they are not made of cells.
They can only reproduce inside host cells – they cannot reproduce independently.
They have a protein coat surrounding their nucleic acid (DNA or RNA).
They carry out no metabolic processes – they do not respire, feed or grow independently.

Examiner tips

Use the exact wording from the mark scheme – e.g. "no cells", "only reproduce inside host cells", "protein coat", "no metabolic processes".
Show each feature as a separate point to match the four marks.
Avoid extra explanation or irrelevant details.

Common mistakes

Confusing viruses with bacteria by stating they are alive or have cells.
Mentioning that viruses can replicate on their own or have metabolism.
Using vague terms like "small" or "simple" instead of the specific features required.

Mark scheme (4 marks)

Viruses have no cells / are not made of cells
Viruses can only reproduce inside host cells / cannot reproduce independently
Viruses have a protein coat (surrounding nucleic acid / DNA or RNA)
Viruses carry out no metabolic processes / do not respire / do not feed / do not grow independently

Key terms in this question

virus