16.3 Plant responses to herbivory Flashcards
what are the physical defences of plants
- thorns
- spiny/hairy leaves
- spikes
- inedible tissue
what are the chemical defences of plants
- tannins
- alkaloids
- terpenoids
- pheromones
how to tannins defend plant
its bitter and toxic to insects it binds to digestive enzymes and inactivates them
how do alkaloids defend plants
it acts as a drug affecting metabolism and poisoning organism
how do terpenoids defend plants
insect repellants/toxins
how do pheromones defend plants
pheromones can be released when a plant is being attacked by insects, the release of pheromones causes neighbouring leaves to produce callose this increases defence against insects
what are VOC’s
volatile organic compounds
similar to pheromones but they facilitate communication between organisms (rather than within different parts of an organism
apple trees produce them to attract predatory mites when attacked by spider mites
wheat seedling use them to repel aphids