Mod. 7 Inq. 2 Flashcards
1
Q
what do passive Defences of plants do
A
prevent infections by physical and chemical barrier
2
Q
What do active defences of plants do
A
prevent further growth of pathogen once infected.
3
Q
Passive defence of plants physical barriers
A
- thick cuticle leaves and cell walls
- stomata can close
- vertical hanging leaves prevent water build up that causes bacterial growth
- bark provides an extra layer
4
Q
Passive defences of plants chemical barriers
A
can produce enzymes that break down the toxins that pathogens produce
5
Q
Examples of active defences in plants
A
- basal resistance
- apoptosis
- systematic acquired resistance (recognition)
6
Q
Basal resistance
A
- activates when pants detect structures associated with pathogens
- living tissue becomes fortified against further infection (gall)
7
Q
Apoptosis
A
programmed cell death to kill off infected tissue and prevent further access for pathogens
8
Q
Systematic Acquired Resistance
A
- release of chemicals during infection that can act as signalling molecules
- helps plant remember a pathogen - reduce subsequent infection
9
Q
Physical responses to pathogens in plants
A
- Bark
- Pectin and lignin in cell walls - reinforce them
- Plants have meristematic tissue in their lignotubers
10
Q
What are lignotubers?
A
woody tissue at the base of the plant
11
Q
Chemical responses to pathogens in plants
A
- cells release hydrogen peroxide, which is toxic to pathogens, and is signalling molecule for other chemical defence mechanisms
- Systematic Acquired Resistance
