fungal growth and development- MR Flashcards
hyphae growth is the defining feature of
filamentous fungi
the termination of polarised hyphal growth is
a key prerequisite for development and pathogenesis
during germination what occurs
switching of growth mode
which two growth mode do fungi switch between
isometric and polarised
two types of hyphae
1) coenocytic or aspirate hyphae
2) septet hyphae
coenocytic/ aseptate hyphae
no septum or pores within the hyphae
septet hyphae
septum and pores which split up the hyphae
complete septa
imperforate
regulated septa
perforate
what is within a simple perforate in Ascomycota
the woronin body
what are septa protected by in Basidiomycota
a cap down as the parenthosome - these septa are called dolipores
dolipores
septa with parenthosomes- basidiomycota
what do septa permit
compartmentalisation of cells and hence differentiation
fungal cell wall role
- maintenance of cell shape
- stabilisation of internal osmotic conditions
- protection against physical stress
- a scaffold for extracellular proteins and secreted enzymes
main proteins in fungal cell wall
- top and thickest layer= mannoproteins
- middle layer- B-1,6-glucan and B-1,3-glucan
- bottom layer- chitin
top layer of fungal cell wall
mannoproteins
bottom layer of fungal cell wall
chitin
what do hyphae contain and what are their role
contain microtubules, connecting compartments and allowing intercellular communication and reallocation of resources.
hyphae tips
- polarised
- can change direction
- show autotropism
when hyphae fuse
anastomose
how can hyphae fuse
- -> tip-tip
- -> tip-side
- -> self fusions and non-self fusion
- -> specialised fusions for sex
specialised fusion for sex are called
clamp connections
hyphae fusion allows for
the formation of complex interconnected networks
what two things drive hyphae extension
1) turgor pressure- closed hydraulic system
2) balanced lysis using the vesicle supply centre (spitzenkorper)
hyphae can differentiate to give
tissues different properties
generative hyphae
hyphae that bear clamp connections or spore
skeletal hyphae
long, unbranched, think or thick walled hyphae
binding hyphae
thick-walled hyphae that branch frequently
a fruit body with only generative hyphae has a
monomitic hypha system
fruit bodies with two or more types of hyphae are called
dimitic or trimitic
skeletal and binding hyphae are usually
empty of cell contents–> thats why polypores are so tough and hard
conidiation
a biological process in which filamentous fungi reproduce from spores
asexual spores are produced by
conidiation
spore are also known as
conidia
growth of spore process
as mother cell grows the oldest spore is muted out, so it is on the end of the chain. Septet form between each spore. the Phialide (mother cell) will be attached to the youngest spore
geiger fungi produce..
complex multi-cellar structures to support spore production
fungal mycelium
Mycelium is the vegetative part of a fungus or fungus-like bacterial colony, consisting of a mass of branching, thread-like hyphae.
fungal mycelium are not resource restricted because they can
expose, capture, exploit, consolidate, combat and disseminate
growth of a mycelium
has a lag phase, exponential phase (unrestricted conditions), linear (content growth rate) and deceleration phases of growth, which occur as conditions become restriction
maturing mycelia become affect dby
nutrient limitation, change in pH and growth inhibitors (metabolic waste products and secondary metabolites that the mycelium produce)
