Mycology Intro Flashcards
What do Fungi have in their cell membranes instead of cholesterol?
Ergosterol
What are yeasts?
Oval, unicellular fungi. They reproduce via budding and form blastospores ( asexual spores ) and may develop pseudohyphae (budding yeast remaining attached)
What are molds?
Fungi that are a multinucleate mass of continuous cytoplasm confined within a series of tubular filaments; growth is by branching and longitudinal extension. (hyphae elongate at theirs tips by apical extension)
What are Coenocytic hyphae?
Hyphae which do not have septate (aseptate)
What are septate hyphae?
Hyphae that possess septa. Septa are cross-walls which are perforated and allow the free passage of (nuclei and) cytoplasm
What are condidia?
asexual spores produced at the tip or side of a hypha
What are conidiophores?
specialized aerial structures that consist of phialides ( aerial hyphae) which produce conidia.
What are sporangiaphores?
specialized aerial structures that produce sporangia- sacs containing asexual spores
What is an arthroconidia?
an asexual spore which is the product of separation and fragmentation of true fungal hyphae
What is the fungal form that reproduces sexually called?
A teleomorph
What is the fungal form that reproduces asexually called?
An anamorph
What is a diagnostic indicator of Candida albicans?
The production of germ tubes
What are pseudohyphae?
Yeasts buds that elongate and remain attached to the parent cell forming chains. Can be differentiated from hypae by their rounded edges.
What are the superficial mycoses?
Malassezia furfur
Hortae werneckii
Piedraia hortae
Trichosporon
What are the cutaneous mycoses?
Trichophyton
Epidermophyton
Microsporum
What are the subcutaneous mycoses?
Acremonium
Fusarium
Alternaria
Cladosporium
What are the systemic mycoses?
Histoplasma
Blastomyces
Coccidioidies
Paracoccidiodes
What are the fungal opportunistic pathogens?
Aspergillus Candida Cryptococcus Pneumocystis Zygomycosis
How do fungi reproduce sexually?
Cells of opposite mating types fuse, the nuclei fuse and chromosomes mix, the chromosome number halves and the cell returns to the haploid state.
What are Basidiomycetes?
Fungi that when they reproduce sexually form a club shaped structure called a Basidium ( formed from the fusion of hyphae).
What are Ascomycetes?
Fungi that when they reproduce sexually create an Ascus from the fusing of hyphae.
What are Zygomycetes?
Fungi that when they reproduce sexually form a zygospore from the fusion of hyphae. When they asexually reproduce they form chlamydoconidia, conidia and sporangiospores contained in sporangia.
What are some examples of Basidiomycetes?
Cryptococcus neoformans,
Malassezia
Trichosporon
(all yeast)
What is Pneumocystidomycetes?
A class within the Ascomycetes phylum. Includes Pneumocystis jirovecii.
What are some examples of Zygomycetes?
Rhizopus
Mucor
What is Saccharomycetes?
A class within the phylum Ascomycetes. Includes Candida and Saccharomyces.
What is Eurtiomycetes?
A class within the phylum Ascomycetes. Includes The dermatophytes and Blastomyces, Histoplasma, Aspergillus, Fursarium, Scedosporium, and Coccidioides.
What are the morphological and reproductive characteristics of Eurtiomycetes?
They are fillamentous with septate hyphae. Utilize asexual conidia borne on specialized structures called conidiophores
What are the morphological and reproductive characteristics of Saccharomycetes?
Budding yeasts and hyphae, pseudohyphae (chains of cells resembling hyphae)
What are the morphological and reproductive characteristics of Pneumocystidomycetes?
Trophic forms and cyst like structures. Fusion of compatible mating types results in a spherical cyst or spore case containing 8 spores.
What are the morphological and reproductive characteristics of Basidiomycetes?
Filamentous forms have hyphae that produce basidiospores in nature. Others are Budding yeasts,
What are the morphological and reproductive characteristics of Zygomycetes?
Molds with Broad, thin-walled coenocytic hyphae and spores contained by sporangium. Have root like structures. in some genera are called rhizoids.
What is a disease caused by Zygomycetes?
Mucormycosis
What is the most widely used staining method for fungi?
Lactophenol Cotton Blue
What growth media additive is required for culturing Malassezia furfur?
Olive oil (or any long chain fatty acid). Due to Malassezia furfur living on the scalp near sebaceous glands.
What is an example of a fungus that requires blood in its growth media?
H. capsulatum
What are the enriched media that should be used if fungi is suspected?
Brain heart infusion ( BHI)
Sabouraud dextrose and BHI ( SABHI
What is Amphotericin B?
A polyene anti-fungal. Works by binding ergosterol and forming pores in the fungal cell membrane.
What is clinically important about Pneumocystis jirovecii?
It causes Pneumocystis pneumonia, which is a key indicator that a patient is immunocompromised (such as those with AIDS)
What is clinically important about Coccidioides immitis?
Causes valley fever. Spores are found in dust and is widespread throughout the Southwestern United States.
