Plant Repsonses To Herbivores Flashcards
(8 cards)
1
Q
Describe physical responses to herbivory
A
- thorns
- spiky leaves
- stings
- inedible tissues
- barbs
2
Q
Chemical responses to herbivory
A
- tannin production
- alkaloid production
- terpenoids
3
Q
Describe what tannins do
A
- when herbivore bites into the plan, tannin is released which has a bitter taste to put animals off
- its toxic to insects as they bind to digestive enzymes in saliva to inactive them
4
Q
What do alkaloids do
A
- group of bitter tasting nitrogenous compounds
-acts as a drug to affect animal metabolism and poisons them - examples are caffeine, nicotine, morphine and cocaine
5
Q
Describe what terpenoids do
A
- produces essential oils and acts as toxins to insects and fungi
- for example pyrethrin acts as a neurotoxin to insects which affects their nervous system
6
Q
What are pheromones
A
- a chemical that affects social behaviour of other members of the same species
- for example; if maple tree attacked by an insect, releases a pheromone which is absorbed by leaves on other branches, these leaves produce callose to protect in case they’re attacked
7
Q
How do pheremones act between themselves and other organism ( produces volatile organic compounds)
A
- volatile organic compound released by plant and diffuses into air around the plant
- for example, when caterpillars attack cabbage, cabbage release chemical signal which attracts a wasp which layers egg inside caterpillar so they’re eaten alive
8
Q
Folding in response to touch
A
- some plants contain alkaloids so if stem is touched they fold down and collapse so it frightens larger hervobores and dislodges insects
- plant returns to normal eventually as a result of k+ ions followed by osmotic water movement
