OCR GCSE Biology B · J257
Paper 1 (Foundation), Paper 2 (Foundation), Paper 3 (Higher), Paper 4 (Higher)
Revise: Non-specific DefencesMucus is therefore a physical defence because it traps pathogens, while cilia help to remove the trapped material.
- Revise: Plant Defences
A structural barrier that helps prevent a pathogen from entering or spreading through an organism.