The body has several kinds of defence against pathogens. Which defences stop pathogens from reaching the alveoli when air is breathed in?
- A1, 2, and 3
- B2, 3, and 4
- C2 and 3 only
- D2 only
Biology 0610 · IGCSE · Diseases and immunity
The body has several kinds of defence against pathogens. Which defences stop pathogens from reaching the alveoli when air is breathed in?