Unit Test #5 – Flashcards
Unlock all answers in this set
Unlock answers| Mycorrhizae |
| increase surface area of fungi with roots of plants; increase water and mineral absorption |
| Saccharomyces |
Baker's/Brewer's Yeast (first eukaryotic cell to have its entire genome sequenced) |
| Hyphae |
| threadlike, branching of mold |
| Dimorphic |
2 forms of temperature dependent fungus: Mold at less than 30?C ("cold mold") Yeast at 37?C |
| Saprobes |
| Molds that decompose dead organisms and recycle their nutrients |
| Contagious fungal pathogens? |
Dermatophytes Candida Pneumocytis |
| True/systemic fungal pathogens? |
Histoplasma Blastomyces Coccidioides Paracoccidioides |
| Opportunistic fungal pathogens? |
Aspergillus Candida Cryptococcus Pneumocytis |
| AIDS defining fungal pathogens? |
Aspergillus fumigates Candida albicans Cryptococcus neoformans (have capsule that prevents phagocytosis) |
| How is fungus diagnosed? |
| Sabouraud dextrose agar |
| Endospores vs. Spores |
Endospores = protection Spores = reproduction |
| Antifungal Therapies? |
Amphotericin B ("gold standard" for antifungal agents; most toxic to humans; not 1st line drug; target ergosterol and punch holes in its cell membrane) Ketoconazole Griseofulvin |
| Blastomyces dermatitidis |
Causes Blastomycosis Cutaneous ulcers causing abscess formation and tissue destruction Pulmonary blastomycosis = most common manifestation in humans; respiratory failure & death in immunocompromised people May lead to cutaneous, osteoarticular, or meningitis in AIDS pt Located around Mississippi River |
| Coccidioides immitis |
Spherules which enlarge and generate more spores Usually asymptomatic (night sweats) Located in dry southwestern states |
| Histoplasma capsulatum |
Most common fungal pathogen affecting humans Carried by bats and humans Located in West Africa and around Mississippi River |
| Paracoccidioides brasiliensis |
Begins in the lungs Disseminates mucous membranes around the mouth Steering wheel shaped pathogen Located in Paraguay and Brazil |
| Aspergillus - fumigates, niger, flavus |
Cause hypersensitivity aspergillosis, noninvasive aspergillomas, acute invasive pulmonary aspergillosis, cutaneous and systemis aspergillosis Aspergillus fumigates = AIDS defining Aspergillus flavus = alfatoxin (liver damage and liver cancer) |
| Candida albicans |
Causes thrush, diaper rash, intertrigo, vaginitis, onchymycosis, ocular candidiasis, and meningitis (in AIDS pt) AIDS defining pathogen |
| Cryptococcus neoformans |
Has capsule prevent phagocytosis From pigeon droppings Causes cryptococcal meningitis (fatal in AIDS pt) AIDS defining pathogen |
| Pneumocytis jiroveci |
Causes pneumocytis pneumonia Common opportunistic fungal infection in AIDS pt |
| Rhizopus sporangium |
| Black bread mold (zygomycota) |
Superficial mycoses: Piedra Malassezia furfur |
Black piedra = Piedraia hortae White piedra = Trichosporon beigelii
Malassezia furfur = pityriasis, folliculitis, and seborrheic dermatitis Tinea versicolor - pityriasis (will illuminate green) |
Common dermatophytoses: Tinea pedis Tinea cruris Tinea unguium Tinea corporis Tinea capitis |
Tinea pedis = athlete's foot/jungle rot Tinea cruris = jock itch Tinea unguium = yellow nails Tinea corporis = ringworm Tinea capitis = cradle cap |
| Sporothrix schenckii |
Rose gardener's disease Nodular lesions |
| Mycotoxicosis |
Aspergillus flavus/mycotoxin/alfatoxin Causes liver damage and liver cancer
Claviceps purpurea = useful product of ergot alkaloids (drugs = Ergometrin & Ergotamine) |
| Mycetimus |
| Mushroom poisoning (Amanita...) |
| Drugs of Choice |
Fungi = Amphotericin B Protozoa = Metronidazole / Flagyl |
| Balantidum coli (B. coli) |
Only ciliate known to cause disease in humans Tx = tetracycline & Flagyl Pigs are the most common host |
| Ameobae: |
(no defined shape) Entamoeba histolytica Naegleria fowleri |
| Entamoeba histolytica |
Causes amebic dysentery Humans are primary host Some humans are asymptomatic carriers No animal reservoir Invades mucosa (voluminous diarrhea & bloody stools) "Night soil" = human feces for fertilizer |
| Naegleria fowleri |
Swimmers inhale contaminated water Migrate to brain and cause amebic meningoencephalitis Coma and death in 4-5 days No Tx |
| Flagellates: |
(at least one flagella) Trypanasoma brucei Trypanasoma cruzi Leishmania species Giardia intestinalis Trichomonas vaginalis |
| Trypanasoma brucei |
Causes Africa Sleeping Sickness Vector = Tsetse fly Leads to meningoencephalitis (drowsiness, coma, and death) |
| Trypanasoma cruzi |
Causes Chaga's disease/American trypanasomiasis Vector = reduviid/kissing/assasin bug Affects heart, esophagus, and large intestine Parasite induced heart disease = leading cause of death in Latin America |
| Leishmania species |
Causes Leishmaniasis Vector = female sand fly Can be cutaneous, mucocutaneous, or visceral |
| Giardia intestinalis |
Common GI disease Causes Giardiasis or "beaver fever" Cysts look like ghosts |
| Trichomonas vaginalis |
Causes STD, Trichomoniasis Cannot live long outside host Men are asymptomatic |
| Apicomplexan parasites: |
Plasmodium - falciparum, vivax, ovale, malariae Toxoplasma gondii Cryptosporidium parvum Cyclospora cayetanensis |
| Plasmodium - falciparum, vivax, ovale, malariae |
Cause malaria Vector = female anopheles mosquito Plasmodium falciparum = worse malaria Merozoites penetrate RBCs and undergo schizogony Mal-aria = bad air; "Swamp smells" Resistant to malaria: Sickle cell (HgbS); HgbC; Glucose-6-Phosphate-dehyrdogenase deficiency; lack of duffy antigen on RBCs |
| Toxoplasma gondii |
Causes Toxoplamosis Cat = definitive host Can cross the placenta Tx: self-limiting; antimalarial drugs |
| Cryptosporidium parvum |
Carried by livestock and poultry From contaminated water Life-threatening in AIDS pt with cholera-like diarrhea |
| Cyclospora cayetanensis |
| In berries, fruits, and vegtables |
| Helminthes parasites: |
Cestodes/tapeworms Trematodes/flukes Nematodes/roundworms Hookworms - ancylostoma duodenale ; Necator americanus Pinworm - Enterobius vermicularis Wuchereria bancrofti |
Cestodes/tapeworms: Taenia solium Taenia saginata Echinococcus granulosus Diphyllobothrium latum |
3 parts = scolex, proglottids, stobila Cysticerci = immature tapeworm Lack digestive system, but absorb soluble nutrients Taenia solium = pig tapeworm Taenia saginata = cow tapeworm Echinococcus granulosus = dog tapeworm (causes hydatid disease with hyatid cysts; has 3 proglottids) Diphyllobothrium latum = fish tapeworm (largest tapeworm) |
Trematodes/flukes: Schistosoma - mansomi, japonicum Schistocoma haematobium Fasciola - hepatica, gigantica |
Snail = intermediate host Cause schistosomiasis/Snail Fever Cercariae = larvae of fluke; cause dermatitis (Swimmer's itch) Lack complete digestive system (no anus) Schistosoma - mansomi, japonicum = live in mesenteric veins; eggs die and calcify leading to fatal tissue damage Schistosoma haematobium = causes urinary tract schistosomiasis; blood in urin; found in Africa and India Fasciola - hepatica, gigantica = infect liver of sheep and cattle
|
Nematodes/roundworms: Ascaris lumbricoides |
Largest nematode to infect humans Most common nematode infection worldwide Causes ascariasis Double route through GI tract |
Hookworms: Ancylostoma duodenale & Necator americanus |
Larvae burrow between toes Causes ground itch |
Pinworm: Enterobius vermicularis |
Most common parasite worm in the US Common s/s = perianal itching Spread via fecal-oral route |
| Wuchereria bancrofti |
Causes filariasis or elephantiasis Infects human lymphatic system Vector = particular genus of female mosquito |
| Arthopod Vector Comparison |
Arachnida = 8 legs (ticks & mites) Insecta = 6 legs; 3 body parts; largest animal group (flea, lice, tsetse fly, mosquito, kissing bug) |
| Yeast vs. Mold |
Yeast = budding reproduction; unicellular Mold = spore reproduction; multicellular |
Intermediate Host vs. Definitive Host |
Intermediate host = carries immature parasites (one or more); asexual reproduction Definitive host = carries mature parasites (always); sexual reproduction |
Parasitologist vs. Mycologist |
Parasitologist = studies infectious diseases caused by protozoa and helminthes Mycologist = studies the diagnosis, management, and prevention of fungal infections |
| How are dermatophytes "an emerging health problem"? |
Dermatophytes are "emerging opportunistic pathogens" Most commonly reported fungal disease Mycoses are localized at sites at or near the surface of the body Found on barber shop clippers and shower room floors |
| What is a "cyst"? |
| Dormant, immotile form that can survive in the environment outside the host for periods of time; can survive adverse conditions, such as lack of food, lack of moisture, unsuitable temps, and toxic chemicals |
| What type of protist must go through the mosquito? |
Plasmodiums & Wuchereria bancrofti |
How are all pathogenic fungi acquired? What are 3 precautions from fungal spores |
Through inhalation of spores
HEPA filters, hoods, and protective clothing |
| What is chitin? |
| Potent antigen to human immune system (contained in fungal cell walls) |
| What is a quorn? |
| Fungal (complete) protein |
