Micro Bio Chp 22 Exam 5
Which of the following is an opportunistic pathogenic fungus in humans?
are normal microbiota for many individuals
Which of the following statements about truly pathogenic fungi that cause systemic mycoses if FALSE?
they have the ability to form mycelial thalli that are very invasive
Which of the following agars is preferred for the culture of fungi?
Sabouraud dextrose agar
Which of the following techniques reveals the presence of fungal cells in tissues?
both KOH treatment and Gomori methenamine silver (GMS) staining
Which of the following is the most common pathogenic fungus affecting humans?
Most mycoses are difficult to treat because
fungicides have numerous side effects, including cross-reactivity to human cells.
All of the true pathogen fungi mentioned in this chapter are
members of the Ascomycota and are dimorphic
Ocular histoplasmosis is an
type I hypersensitivity immune reaction
What is the diagnostic structure produced by Paracoccidioides brasiliensis?
"steering wheel" or "captains wheel" buds visible microscopically
an elderly woman is experiencing fever, chest pain, difficulty breathing and a cough that occasionally brings up mucus containing blood. She reports having visited family in rural New Mexico over the Labor Day weekend. a GMS-stained sample from her lungs shows the presence of large spherules. Which of the following is the most likely infecting agent?
Which of the following statements about Candida is FALSE?
it is easily treated with topical antifungals in immunocompromised patients
An avid agrdener in eastern North America begins to have a fever and cough. A sample from her lungs contains yeast cells. She may be infected with
The most common disease produced in humans by Cryptococcus is
Which of the following fungal infections was rare prior to the AIDs epidemic?
Pneumocystis jiroveci is
an obligate parasite that cannot survive outside the lungs
An immunocompromised patient has a severe nasal infection that has blocked his ability to breathe through his nose. A sample is taken from the nose is treated with KOH and is found to contain large hype with very few septa. Which of the following diseases may the the patient have?
Several new fungal opportunists have been found to infect AIDs patients including
Ringworm is caused by
dermatophytes growing in the outer dead tissue layers of the skin (epidermis).
is an intracellular parasite
Which of the following dermatophytes infects hair as well as skin?
White patches on the surface of the tongue and the oral mucosa accompanied by inflammation and swelling are signs consistent with
Which of the following fungal infections may progress to infection of the brain?
Coccidioides immitis, Cryptococcus neoformans, and Mucor
Superficial mycoses are more common that cutaneous and subcutaneous mycoses because
only a few fungi are invasive
A sample of the tissue from an inflamed pus-filled area on the lower leg is treated with KOH and stained with GMS. Under the microscope golden brown spheres are visible. With what disease are these observation consistent?
Which of the following fungal infections can be contracted through thorn pricks or wood splinters?
Which of the following statements about Malassezia is FALSE?
It causes phaeohyphomycosis
The monomorphic fungus Rhizopus is a
common bread mold and an opportunistic pathogen
Mycetisumus is caused by
ingestion of toxic mushrooms
Which of the following is referred to as the "death cap" mushroom?
Which of the following is a false morel that causes bloody diarrhea, convulsions, and death within two days?
Ergometrine, which is used to stimulate labor contractions, is a product of
Which of the following statements is true of mycotoxicosis but NOT mycetismus?
the fungus is not present
Psilocybin is a
toxin that acts as a hallucinogen
Chronic inhalation of particular fungal allergens would lead to an
type III hypersensitivity reaction
The subcutaneous infection known as ______ can produce a series of lesions spreading from the initial infection point resulting from the fungus' ability to invade the lymphatic vessels
Chronic low-level ingestion of ______ may cause liver cancer.
Brown pigmented hyphae in specimens from cutaneous or subcutaneous lesions are characteristic of
Which of the following contributes to the pathogenesis of Cryptococcus neoformans?
the production of melanin and the presence of a phagocyte-resistant capsule
Injuries wich introduce _____ into the subcutaneous tissuey result in mycetoma, a tumor-like abscess containing pus and fungus.
Pityriasis, characterized by patches of hyper pigmented and depigmented skin on the trunk and arms is due to cutaneous infection with
Infection of the skin by Trichophyton rubrum results in raised red scaly patches of skin, a condition known as
Which of the following produces a hallucinogenic toxin?
The fungus _____ produces toxins which have beneficial clinical applications.
Agricultural workers may develop respiratory problems resulting from _____ responses to fungal allergens.
either type I or type II hypersensitivities
Most fungi exist as (parasites/ sparse/ autotrophs) and function as the major decomposers of organic material.
Infections with (dermatophytes/ pathogens/ opportunists) are commonly acquired by person -to-person direct contact.
the true pathogenic fungi responsible for systemic mycoses have (dimorphic/ monomorphic/ polymorphic) growth characteristics.
A solution of (GMS/ KOH/ DIF) is used to dissolve keratin and cellular material in skin scrapings, leaving only the fungal cells for examination.
The best strategy for preventing fungal disease is (avoidance/ vaccination).
The cell walls of fungi contain (cholesterol /ergosterol) which is a target of some anti fungal treatments.
Blastomyces dermatitidis occurs in the (eastern/ central/ southwestern/ western) part of North America.
The anti fungal agent (azalea/ echiocandins/ griseofulvin) interferes with microtubule formation and chromosome separation.
The presence of (hyphae/ spores/ spherules) in a sample from the lungs is diagnostic for coccidioidomycosis.
Paracoccidioidomycosis occurs in Mexico and (North/ south) America.
The production of distinctly (smooth/ bumpy/ spiny) spores is diagnostic for Histoplasma capsulate.
Exposure to (Aspergillus/ Candida/ Microsporum) species most commonly causes only allergies.
Clusters of budding yeast and branching pseudohyphae are consistent with (candidiasis/ dermatophytosis/ pityriasis).
The opportunistic infection known as (aspergillosis/ cryptococcosis/ sporotrichosis) may develop into a series of nodular, pus-filled lesions on a limb.
Chronic infections of Malassezia furfur result in (pityriasis/ringworm).