Mycology Flashcards
3 principal parts of Fungi
1 Nucleus
2 Cytoplasm or plasma membrane
3 Rigid cell wall
Most fungi are
obligate or facultative aerobes
True or False: Fungi are chemotrophic
Fungi that possess a polysaccharide capsule
Cryptococcus neoformans
Function of cell wall and capsule
Protection
Transport of substances
Involved in host response
Basic forms of fungi
Yeast and molds
may reproduce either asexually or sexually
DIMORPHIC FUNGI
All fungi, with the exception of yeast, are composed of filamentous or tube-like filaments called
HYPHAE
CLASSIFICATION Hyphae/Hypha
Aseptate/Coenocytic Hypha
No cross-walls/division
Ex. Zygomycetes (Rhizopus and Mucor)
Septate Hypha
With cross-walls/ division
All fungi except Zygomycetes
Types of Hyphae: Favic Chandelier
Moose Antlers
Types of Hyphae: Rhizoids
Root like
Types of Hyphae: Racquet
Club shape
Types of Hyphae: Spiral
Tightly coiled
Types of Hyphae: Pectinate
Broken Comb
The mass of growing hyphae
Mycelium
3 types of mycelium
-Aerial Mycelium
-Reproductive Mycelium
-Vegetative/Thallus Mycelium
Portion projecting above the
substrate and capable of forming the spores
Reproductive
Mycelium
Penetrates into the substrate
and absorbs food
Vegetative/Thallus
Mycelium
Unicellular fungi which reproduce by budding
Yeasts
Example of yeast
Cryptococcus neoformans (capsulated yeast)
Grow partly as yeasts and partly as elongated cells resembling hyphae which are called
pseudo hyphae
Example of pseudo hyphae
Candida albicans
Produces creamy colonies resembling bacterial colonies
Yeast
Cottony mycelial mass
Mold
Form true mycelia & reproduce by formation of different types of spores.
Molds/ Filamentous fungi
Vegetative/ aerial hyphae
Example of molds/filamentous fungi
Rhizopus and Mucor
capable of single growth phase
Monomorphic
Example of monomorphic
Sepedonium
capable of 2 growth phases
Dimorphic
Grow in room temp 22-25degreeC
Molds
Grow in body temp 37degreesC
Yeast
Example of yeast
Sporothrix schenckii
Blastomyces dermatitides
Histoplasma capsulatum
Paracoccidioides brasiliensis
both mold and yeast phase in the sam culture
Polymorphism
Example of polymorphism
Exophiala spp
Nuclear division and reduction resulting in the formation of haploid nuclei without the cytoplasm
Chromosome number contained with haploid nuclei is 1⁄2 the number of chromosome in the mother cell
Meiosis
Division of nuclear chromosome and
cytoplasm resulting to 2 daughter cells
Mitosis
Characterized by feeding or trophic activities and also in the absorption of nutrients
Somatic phase
2 general types:
◦ Asexual or Imperfect State (Anamorph)
◦ Sexual or Perfect State (Telemorph)
Reproductive Phase
2 general types of Reproductive phase
Asexual or Imperfect State (Anamorph)
◦ Sexual or Perfect State (Telemorph)
carried out by specialized fruiting structures known as CONIDIOGENOUS cells.
Asexual reproduction
TWO COMMON CONNIDIOGENOUS
CELLS
PHIALIDES: vaselike strutures that produce phialoconidia
ANNELIDES: rringed structures that produce annelloconidia
vaselike strutures that produce phialoconidia
PHIALIDES
rringed structures that produce annelloconidia
ANNELIDES
Imperfect Fungi (cannot reproduce sexually)
Asexual spores
Perfect Fungi (can reproduce sexually)
Sexual Spores
Arise from the side of the hyphae
Conidia
– appear small and unicellular (Asexual spores; Conidia)
Microconidia
large and multicellular (Asexual spores; Condidia)
Macroconidia
Derived from simple budding
Blastoconidia
– thick-walled spores that are formed during
unfavorable conditions;
Chlamydoconidia
@ tip of the hyphae
Terminal Chlamydoconidia
whithin the hyphal
strand
Intercalary Chlamydoconidia
@ the side of the hyphae
Sessile Chlamydoconidia
“Arthro” – joint (appear jointed)
Derived from fragmentation of mycelium Barrel-shaped or rectangular spores Disjunctor cell – empty cell between each spore Fungi with arthroconidia
Arthroconidia
Fungi with arthroconidia
Coccidioides immitis
Geotrichum candidum
Asexual spores are enclosed in a sporangium borne on a specialized hypha known as a
sporangiophore
4 classes based in sexual spore formation
Zygomycetes
Ascomycetes
Basidiomycetes
Deuteromycetes (fungi imperfectii)
A fungus that reproduces sexually known as
teleomorph
asexual formed
ANAMORPH
more than one anamorph is present for the same teleomorph
SYNANAMORPH
◦ Enclosed in a sac-like structure called ascus
◦ 2-8 spores
Ascospores
Derived from the fusion of 2 identical spores from the same hypha
Zygospores
Derived from the fusion of 2 cells from non-identical separate hyphae
Oospores
Enclosed in a club shaped structure called basidium
Basidiospores
●Group of fungi whose sexual phases are not identified.
●Grow as molds as well as yeasts.
●Asexual stage – conidia
e.g. Candida, Cryptococcus
Deuteromycetes or Fungi mperfectii
Asexual stage of Deuteromycetes or Fungi imperfectii
Conidia
Example of Deuteromycetes or Fungi mperfectii
e.g. Candida, Cryptococcus
Include fungi that are not completely classified due to the absence (not recognized) of sexual state
FUNGI IMPERFECTI
Example of FUNGI IMPERFECTI
These include Candida, Torulopsis and Epidermophyton
often opportunistic pathogen in immunocompromised patients.
Produce profuse gray to white, aerial mycelium characterized by the presence of sparsely septate hyphae
Asexual reproduction is characterized by the presence of sporangiophores and sporangiospore
Sexual reproduction is zygospores
Zygomycota
Common zygomycetes includes:
MUCOR, RHIZOPUS AND ABSIDIA
Sexual reproduction of zygomycota
Zygospores
Characterize by the production of sexual spores known as ASCOSPORES
Formed within a saclike structure known as an ASCUS
ASCOMYCOTA
ASCOMYCOTA example
MICROSPORUM SPP;
TRICHOPHYTON SPP; PSEUDOLLESCHERIA SPP.
One clue that a mould is basidiomycetes is the presence of
CLAMP CONNECTIONS