Formerly Zygomycota Flashcards
What are the 4 recognized clades (subphyla) Zygomycota? What is their evolutionary origin?
Mucoromycotina
Entomophthoromycotina
Kickxellomycotina
Zoopagomycotina
this unrecognized phylum is polyphyletic (of different origins) but each clade is monophyletic - ie., the clades are not necessarily closely related, but the organisms within the clades are of single evolutionary origin (i think)
What are the common lifestyles for Zygomycota?
many are saprophytes that degrade wide range of substrates (plant and animal)
many are primary colonizers of substrates with simple carbon sources
some are highly specialized parasites and pathogens
Describe the common morphology of the mycelium for Zygomycota
haploid mycelium often multinucleate and nonseptate but can become septate
Which is the more dominant life stage for Zygomycota?
usually haploid vegetative (asexual) mycelium
short-lived or restricted diploid phase - may be just resting
What environments are Zygomycota found in?
mostly terrestrial but some are aquatic (usually parasites)
Do Zygomycota have motile spores?
no flagellum
what is the lifestyles for subphylum Mucoromycotina?
saprophytes, parasites
rapid, early colonizers
abundant asexual spore production
what is the reproduction strategy for subphylum Mucoromycotina?
mostly heterothallic, some homothallic
both asexual and sexual stages but sexual spores are persistent (zygospores or zygosporangium)
Describe the sexual phases of the life cycle for Mucoromycotina
no distinct morphology for haploid mycelia
anamorphs fuse (haploid mycelia) = zygospore (teleomorph)
plasmogamy then karyogamy = diploid cell (zygospore)
thick wall forms around it
Give an example of subphylum Mucoromycotina
Rhizopus stolonifer
What is a zygosporangium?
the structure that produces the releases haploid hyphae that will produce sporangiophores
this structure can be used to ID species
What are sporangiophores?
the sporangia that produce the haploid mycelium
modified hyphae
What are gametangia?
the sexual organs that produce gametes
What is a zygospore?
the thick-walled resting (diploid) cell
product of sexual reproduction
What structure can be used for species ID in Mucoromycotina?
Zygosporangia
WHat produces asexual sporangiospores in Mucoromycotina?
sporangia located at the end of the sporangiophores (modified hyphae)
How do Mucoromycotina most commonly exist (in what form)?
asexual phase most common and will exist and grow as long as nutrients are sufficient
What purpose does the zygosporangia provide for Mucoromycotina?
the zygosporangia produces the thick-walled persistent zygospore which can survive adverse conditions
the zygosporangia also undergoes sexual reproduction which increases genetic variation
What is the main purpose of the anamorph/asexual stage of Mucoromycotina?
dispersal - huge diversity for different ecologies and species
Give an example of how dispersal is key to the Mucoromycotina anamorphs and the diversity of strategies
Pilobolus - the hat thrower:
phototrophic sporangiophores, ejects spores out of sporangia up to 2 meters away to land on vegetation to be consumed by herbivores and pooped out elsewhere and colonize the poop
What is phototrophic dispersal?
a method of dispersal in which the sporangiophore aims the sporangia toward the sun with a subsporangial vesicle and builds turgor pressure to eject the sporangia
What lifestyles does subphylum Entomopthoromycotina have? give an example of a species and its host
insect pathogens - ‘ENTOmology ‘ = insect
‘entomophthora’ = ‘insect destroyer
ex. Entomopthora muscae infects house flies with sticky sporangiospores
What lifestyles does subphylum Kickxellomycotina have?
saprobes - soil or dung
can recolonize substrates
How does the morphology of subphylum Kickxellomycotina hyphae differ from other Zygomycetes?
unlike other Zygomycota, which do not have hyphal septa, Kickxellomycotina usually have regular septa
