Plant Active Defences

Question 1

Definition

Answer 1

Can detect chemicals in the cell wall of pathogens. Plants respond by fortifying existing defences and releasing chemicals.

Question 2

Fortifying existing defences

Answer 2

More cellulose in cell wall
Callose deposition between cell membrane and cell wall
Necrosis (cell suicide in infected part of plant to prevent spread)
Canker (death of woody tissue)

Question 3

Terpenoids

Answer 3

Range of existing oils with antibacterial and anti fungal properties

Question 4

Phenols

Answer 4

Have antibacterial and anti fungal properties

Question 5

Alkaloids

Answer 5

Bitter taste to prevent damage by animals so less transmission. May inhibit a variety of metabolic reactions.

Question 6

Defensive proteins

Answer 6

Stop reactions in pathogen by inhibiting membrane ion channels. Rich in cysteine.

Question 7

Hydrolytic enzymes

Answer 7

Chitinases - break down chitin in fungal cell walls.
Glucasases - hydrolyse the glycosidic bonds in glucans.
Lysozyme- degrade bacterial cell walls