How can plants physically defend themselves from disease?
Plants have tough cellulose cell walls, tough waxy cuticle on leaves, and thick layers of dead cells around stems (bark) which can fall off. These prevent microorganisms from invading.
How can plants chemically defend themselves from disease?
Plants contain antibacterial chemicals which can kill invading bacteria, and poisons to deter herbivores from grazing on them (eg, cyanide).
What are the mechanical adaptations to prevent disease?
Thorns and hairs on plants deter grazers. Some plants have leaves which droop or curl when touched. Some plants mimic insects to prevent them being grazed.
