Processes Flashcards
1
Q
Appressorium function
A
- Germ tube emerging from spore recognises it is on leaf surface and triggers appressorium formation
- The tip of the germ tube ceases polar growth, hooks and begins to swell
- Nutrients including lipids and glycogen transported from the conidia into the appressorium
- Metabolised into glycerol and trehalose
- This generates a high turgor pressure (5-8MPa) to push peg through cuticle
2
Q
What are 3 methods fungi use to obtain nutrients from cells?
A
- Secrete proteins to cause nutrient leakage
- Necrotrophs cause cell wall degradation and cell lysis
- Haustoria: specialised feeding structures for nutrient uptake
3
Q
What is a sclerotia?
A
A resting body for fungal survival during dormancy
4
Q
Agrobacterium transfer of Ti plasmid
A
- VirA (receptor) detects polyphenolics released from wounded plant cell
- VirA combines to VirG (transcriptional activator) which switches on expression of all the vir genes
- Vir genes in Ti-plasmid responsible for DNA transfer
- DNA cut out of plasmid, wrapped in proteins and sent through transport machinery out of bacterial cell, across plant cell wall and into cytoplasm
- DNA transported into nucleus through a plant transported
5
Q
How doesErwinia amylovora infect apple trees by insects?
A
Bees carry bacteria to flowers
Bacteria penetrate flowers through nectarthodes
