12.4 plant defences against patoghens

What physical barriers do plants have to prevent pathogens getting in?

waxy cuticle, bark and cellulose wall

Why do plants seal off and sacrifice diseased tissues?

Because they are continually growing at the meristems

what do receptors cells in plants do during pathogens attacks?

They respond to molecules from the pathogens or two chemicals produced when the plant cell wall is attacked, stimulating the release of signaling molecules that appear to switch on genes in the nucleus which in turn trigger cellular responses such as producing chemicals and sending alarm signals to unaffected cells to trigger their defence.

Examples of insect repellents?

Pine resin, citronella

Example of insectides?

Caffaine which is toxic to insects

Example of antibacterial compounds?

Antibacterial gossypol which is produced by cotton plants

Example of anti fungal compounds?

Chitinases which are enzymes that break down the chitin in fungal cell walls

Example of general toxins?

Cyanide which is toxic to most living things