Week 10 - Defence

Question 1

2 types of plant defence?

Answer 1

Constitutive (passive) and induced (active)

Question 2

hypersensitive response (HR)

Answer 2

rapid cell death around site of attack, sealing off the wounded tissue to prevent the pathogen form moving

Question 3

Antimicrobial agents produced during HR are?

Answer 3

Hydrogen peroxide and nitric oxide, as well as Phytoalexins

Question 4

reactive oxygen species?

Answer 4

Hydrogen peroxide (H2O2) and superoxide anion (O2)

Question 5

What do ROS do?

Answer 5

they are toxic to microbial invaders, and catalyse oxidative cross-linking of the cell wall they also signal other defence responses,

a.k.a. they are cool

Question 6

Hydrogen peroxide?

Answer 6

Produced by by plant cells, reinforces the walls of cells surrounding the infection creating a barrier and inhibiting the spread

Question 7

Phytoalexins?

Answer 7

Antimicrobial, low molecular weight, active against wide range of organsims, induced by microbial challenge

Question 8

Systemic acquired resistance? (SAR)

Answer 8

allows a plant to respond quickly to a second attack, induction of genes called pathogenesis related

Question 9

MAMP-triggered immunity (MTI)

Answer 9

Receptors on cell wall identify pathogens, send signals which results in strengthening of the cell wall, stopping the pathogen

Question 10

Pathogens way around MTI?

Answer 10

The cell can forget the pathogens features, or use effector proteins to turn off the cell MTI

Question 11

Effector-triggered immunity (ETI)

Answer 11

is the defences answer to effector proteins, R protein recognise the E protein fighting it

Question 12

The gene for gene model