IB Biology HL 2.3.1 Common Structural Features of Viruses
Practise IB Biology HL 2.3.1 by identifying viral structure and explaining why viruses depend on host cells for replication.
- Syllabus
- First assessment 2025
- Course
- Biology HL
- Level
- HL
Practise IB Biology HL 2.3.1 by identifying viral structure and explaining why viruses depend on host cells for replication.
The table shows the number of amino acids that are different in the sequences of the protein FOXP2 from a human compared with four other primate species.

Some infectious diseases in humans are caused by viruses that originated in other primates.
State one structural feature of a virus.
small/fixed size;
nucleic acid/DNA/RNA;
capsid (made from protein);
no cytoplasm;
few or no enzymes;
attachment protein;
Marking guidance:
Do not accept genetic material.
1 max