Introduction to Fungi 1 Flashcards
<p>What can fungi infect?</p>
<p>Plants</p>
<p>Insects</p>
<p>Amphibians</p>
<p>Mammals</p>
<p>What is fungas?</p>
<p>A chemo-organotrophic eukaryoate that lacks chlorophyll and forms spores</p>
<p>What does the cell wall of fungus contain?</p>
<p>Polysaccharides</p>
<p>Often chitin or glucan which absorbs nutrients</p>
<p>What is the classification based on?</p>
<p>Morphology (shape)</p>
<p>What do we informally refer to fungi as?</p>
<p>Moulds, yeasts or mushrooms</p>
<p>What are the 3 groups of fungus?</p>
<p>Basidomycetes</p>
<p>Ascomycetes</p>
<p>Zygomycetes</p>
<p>What is the sexual and asexual spore of basidomycetes?</p>
<p>Sexual spore is basidospore</p>
<p>Asexual spores is conidum</p>
<p>What is the sexual and asexual spore of ascomycetes?</p>
<p>Sexual spore is ascospore</p>
<p>Asexual spore is conidium</p>
<p>What is the sexual and asexual spore of zygomycetes?</p>
<p>Sexual spore is zygospore</p>
<p>Asexual spore is sporangiospore</p>
<p>What are examples of basidomycetes?</p>
<p>Mushrooms</p>
<p>What are examples of ascompycetes?</p>
<p>Neurospora</p>
<p>Saccharomyces</p>
<p>What are examples of zygomycetes?</p>
<p>Bread moulds</p>
<p>What are examples of basidiomycete pathogens?</p>
<p>Mucor</p>
<p>Rhizopus</p>
<p>What are examples of ascompycete pathogens?</p>
<p>Cryptococcus</p>
<p>Malassezia</p>
<p>What are examples of zygomycete pathogens?</p>
<p>Candida</p>
<p>Histoplasma</p>
<p>What is in the structure of a basidiomycete?</p>
<p>Basidospores</p>
<p>Sterigmata</p>
<p>Septum</p>
<p>Hypha</p>
<p>What is contained in ascomycetes and where?</p>
<p>Ascospores contained within a sac</p>
<p>What is the structure of a zygomycete?</p>
<p>Rough walled zygote, contains one or more zygospore</p>
<p>What are yeasts?</p>
<p>Fungi that favours a unicellular habit</p>
<p>What are examples of non-fetal diseases caused by fungi?</p>
<p>Athletes foot (caused by epidermophyton)</p>
<p>Thrush (caused by candida spp)</p>
<p>Pityriasis versicolor (caused by malassezia spp)</p>
<p>What is athelete's foot caused by?</p>
<p>Epidermorphyton</p>
<p>What is thrush caused by?</p>
<p>Candida spp</p>
<p>What is pityriasis versicolor caused by?</p>
<p>Malassezia spp</p>
<p>What are dermatophyte infections?</p>
<p>Fungi have enzymes that degrade and utalise keratin as a nutrient source which is caused by epidermorphyton</p>
<p>What is degrading and utilising keratin as a nutrient known as?</p>
<p>Dermatophytosis</p>
<p>What are 3 fungi that cause skin disease?</p>
<p>Epidermophyton floccosum</p>
<p>Microsporum canis</p>
<p>Trichophyton mentagrophytes</p>
<p>What is pityriasis versicolour?</p>
<p>A yeast infection that also forms hyphae in infected skin</p>
<p>What are examples of fungi that can cause fatal disease?</p>
<p>Candida spp</p>
<p>Asperigillus spp</p>
<p>What does candida spp do?</p>
<p>Infects deep organs of patients with immune dysfunction</p>
<p>What does asperigllus spp do?</p>
<p>Infects deep organs of patients undergoing chemotherapy or stem cell transplantation</p>
<p>What are host factors that contribute to pathogenicity of fungal infections?</p>
<p>Favourable micro environments (warm, moist areas)</p>
<p>Broad antimicrobial agents reduce competition</p>
<p>Immunosuppresion creates window of opportunity for fungal infection</p>
<p>What can immunosuppresion of hosts be?</p>
<p>Iatrogenic (illness caused by treatment)</p>
<p>Disease processes</p>
<p>What are iatrogenic causes of immunosuppresion?</p>
<p>Steroids</p>
<p>Chemotherapy</p>
<p>Organ transplantation</p>
<p>What is iatrogenic?</p>
<p>Illness caused by treatment</p>
<p>What are disease processes that cause immunosuppresion?</p>
<p>AIDS</p>
<p>Leukaemia</p>
<p>What kinds of infections do candida infections cause?</p>
<p>Oral</p>
<p>Vaginal</p>
<p>Skin</p>
<p>Nail</p>
<p>Urinary tract</p>
<p>What kinds of fungi are the candida spp?</p>
<p>Yeasts</p>
<p>What is dissemination?</p>
<p>Spreading</p>
<p>What is the process of dissemination of candida spp?</p>
<p>1) Part of normal commensal gut flora</p>
<p>2) Antibacterial drugs wipe out competition</p>
<p>3) GI tract wall damaged</p>
<p>4) Spreads through blood</p>
<p>What is hyphae?</p>
<p>Long branching structure of a fungi</p>
<p>What is aspergillosis caused by?</p>
<p>Aspergillus spp</p>
<p>What diseases does aspergillosis lead to?</p>
<p>Asthma</p>
<p>Aspergilloma</p>
<p>What is the process of aspergillosis infecting?</p>
<p>1) Inhaled</p>
<p>2) Forms hyphae in lung tissue</p>
<p>3) Invades blood vessels</p>
<p>What is cryptoccososis caused by?</p>
<p>Cryptococcus spp</p>
<p>What are the cryptococcus spp?</p>
<p>Yeasts with a capsule</p>
<p>What diseases does cryptoccososis lead to?</p>
<p>Pulmanory cryptococcosis</p>
<p>Meningitis</p>
<p>Disseminated infection in severely compromised hosts</p>
<p>Why is too much and too little immunity to fungi a bad thing?</p>
<p>Too much leads to a hypersensitive response and too little leads to infection</p>
<p>How is fungi diagnosed?</p>
<p>Histopathology (under the microscope)</p>
<p>High resolution CT scan</p>
<p>What are the 3 main classes of anti-fungal drugs?</p>
<p>Triazoles (target steroids)</p>
<p>Echinocardins (target walls)</p>
<p>Polyenes (target membranes)</p>
<p>What do triazoles target?</p>
<p>Steroids</p>
<p>What do echinocandins target?</p>
<p>Cell wall</p>
<p>What do polyenes target?</p>
<p>Membrane</p>
<p>What are common problems with anti-fungal drugs?</p>
<p>Targets are not broad enough</p>
<p>High toxicity</p>
<p>How do triazoles work?</p>
<p>Inhibit production of sterols by targeting enzymes (Erg11)</p>
<p>What is an issue with triazoles?</p>
<p>Resistance has been developed my mutation of Erg11 which pumps the drug out</p>
<p>How do polyenes work?</p>
<p>Form pores in the cell wall that cahnges the internal environment and kill the fungi</p>
<p>How do echinocandins work?</p>
<p>Inhibit glucose synthesis to prevent glucans being made, which weakens the cell wall and they cannot grow</p>
<p>What is a problem with echinocandins?</p>
<p>Resistance is acquired by mutations of enzymes</p>
