Basidia, Basidiospores, Hyphae & Mitospores Flashcards
mitospores
spores produced by mitosis, asexual spores
no plasmogamy, karyogamy or meiosis involved
homobasidiomycota
produce basidia that are non-septate
heterobasidiomycota
produce basidia with septate
what is the classification of basidia among heterobasidiomycota?
chiastobasidium
stichobasidium
chiastobasidium
formation of septae across the basidia, horizontal septation
what genera are chiastobasidium?
uredinales (rusts)
ustilaginales (smuts)
Auriculariales (ear fungi)
stichobasidium
septations run parallel to the vertical axis (vertical septation)
what genus is stichobasidium?
Tremellales (jelly fungi)
when does the probasidium form?
before septation
when a metabasidium has formed, what processes have already occured?
karyogamy & meiosis
what are the 4 parts of a basidium?
probasidium
metabasidium
wall layers
sterigma
where do the diff types of septations form in heterobasidiomycetes?
metabasidium
what are the wall layers of the basidium?
internal layer
external pellicle
where does sterigma extend from?
metabasidium wall
protosterigma
base of sterigma
hilum
region of the spore where the spore meets the tip of the of sterigma, seen as a mark or scar on the apiculus or hilar appendix
what structure is required for spores to catapult?
hilum
what is the role of the hilar droplet?
accumulates water & builds up moisture
what is the hilar droplets source of water?
cystidia, cystidioles & paraphyses
cystidia
cells found in b/w basidia, contain water
paraphyses
support structures found in the hymenium
where is the osmotic substance located? & what is it?
tip of the sterigma & base of the spore
sugar alcohol
jelly fungi have what type of septation?
stichobasidia
what type of septation does Tulasenallaceae have?
chiastobasidia
epibasidia & where is it found?
long, outgrowths at the top of the basidium, bearing basidiospores
each epibasidia produces a spore
Tulasnellales
ear fungi have what type of septation? & what is their order?
chiastobasidium
auriculariales
teliospore
produced in a closed structure on the host (wheat)
where are teliospores produced?
telium
a teliospore is ___ celled & each cell has ____ haploid nuclei
2
2
what do teliospores form?
promycelium which develops into a basidium
how many basidia form per teliospore?
2
what does the presence of sterigma indicate?
karyogamy & meiosis have occurred
what structure isn’t formed in rusts?
hymenium
what host do basidiospore infect?
barberry
what are the 2 hosts of rusts?
wheat & barberry
how is migration facilitated in rusts?
through E sources, method of acquiring alternative food sources
In rusts, basidia come directly from a ______, there is no ______
spore
hymenium
what are the steps in basidium development?
- Clamp connection forms
- Gamete nuclei are in a common septate
- Karyogamy & vacuolar development
- Apical cap, basal vacuole, meiosis & initial sterigma formation
- Sterigma development, swelling of basal vacuole & development of spore initials
- Extrusion of nuclei into developing spores
- Mature spores on sterigma
when the sterigma tip inflates there is an extension of what 2 layers?
internal basidial layers
external basidial pellicle
wall layers def
protoplast boundary to exterior covering of the wall
what are the wall layers
endosporium
episporium
exospordium
perisporeium
ectosporium
what are the spore regions
germ pore
hilar depression
hilar appendix
hilum
germ pore
region of the spore from which germination occurs
not all basidiospores have pores
hilar depression
important for dissemination of spores, concave side providing lift
hilar appendix (apiculus)
projection of the spore which connects it to the sterigma
region in which there is a point of humidity that can interact with the osmoticum (hilar droplet)
hilum
mark or scar on the apiculus or hilar appendix at the point of attachment to the sterigma
what point of the spore interacts with the osmoticum
hilar appendix/apiculus
how is the spore shape produced?
elasticity of the wall & turgor pressure within the spore
describe how basidia sit on sterigma
sit on a slight angle, weakly towards the vertical axis of the basidium
buller’s droplet
swelling water droplet forms at the base of the spore, at the junction with the sterigma
describe the surface tension catapult mechanism
Sudden change in the osmoticum in the spore causing water to spread all over the spore
Spore covered with a liquid film
When Buller’s droplet fuses with a film of liquid on the surface of the spore, a shift in mass occurs causing the center of gravity to change
Buller’s drop causes the change in center of gravity
Tension on the sterigma is released, it springs back & catapults the spore
when does the sterigma spring back?
when the tension is released
statismospores
static, no catapulting, no convex & concave sides of the spore
what families have a statismospore release method?
russulaceae
lactariaceae
ballistospore
forcible discharge (catapulting)
what type of fungi have ballistospore dispersal method?
agarics (catapulting occurs on gills)
describe the path of travel spores take when catapulted
not parabolic traveling, a sporabola: this path is taken due to the concave & convex sides of the spore
the concave side providing lift causes the spore to travel parallel with the ground for some time
what causes the sporabola pathway?
spore shape
specific gravity
surface tension catapulting occurs in:
Typical mushrooms
Jelly fungi
Rust fungi
Some yeasts
catapulting steps
A. Spores are asymmetrically oriented on the sterigmata
B. Mannitol & hexoses are secreted from the base of the spore & a film of water surrounds the spore. A water droplet appears seconds before discharge shifting the center of gravity
C. The water film & droplet combine causing a rapid displacement of the spore’s center of gravity. The shifted mass is opposed by the sterigma which is under high turgor pressure & elastic force. With rapid movement of water away from the apiculus & sudden release of turgor pressure in the sterigma the spore is catapulted away in the direction of the displaced center of gravity.
what process is required for hyphae to go from being momokaryotic to dikaryotic?
plasmogamy
what type of plasmogamy is used in basidiomycota
somatogamy
heterothallic
requires 2 sexually compatible nuclei
spermatization
Form spermatia which fertilize the receptive hyphae from a spermatogonium from the opp mating type
somatogamy
fusion of hyphae of the opp mating type
describe the dolipore septum of Ustilaginales & Uredinales
undeveloped
describe the parenthosome of Ustilaginales & Uredinales
unperforated
describe the parenthosome of the agaricales
perforated
describe the parenthosome of Auriculariales
unperforated
describe the parenthosome of Tremellales
series of chunks, very large pores
