Exam 1

Question 1

Are fungi classified as eukaryotic or prokaryotic?

Answer 1

eukaryotic

Question 2

What is the structural element that comprises a fungus?

Answer 2

hyphae

Question 3

Which class of fungi has a non-septate mycelium?

Answer 3

Zygomycetes/phycomycetes

Question 4

Why are certain fungi classified as “Fungi Imperfecti”?

Answer 4

lack sexual phase, or their sexual phase is unknown

Question 5

How does the function of reproductive mycelia differ from that of vegetative mycelia?

Answer 5

vegetative mycelium grow below the surface of the medium and anchor the fungus secretes enzymes making them able to absorb nutrients; reproductive mycelium project above the surface of the medium, this is where spores are located

Question 6

To which class do most pathogenic fungi belong?

Answer 6

Deutermycetes

Question 7

What term best describes the nutritional characteristics of fungi?

Answer 7

saprophytic/saprotrophic

Question 8

Are fungi aerobic or anaerobic?

Answer 8

aerobic

Question 9

What is the best single medium for the primary isolation of fungi?

Answer 9

Sabouraud’s dextrose agar (SBA/Sabs)

Question 10

What is the purpose of corn meal agar?

Answer 10

nutritionally deprives the organisms so that sporulation will occur

Question 11

How long should routine fungal cultures be held before being discarded?

Answer 11

minimum of four weeks

Question 12

What three things does the mounting medium lactophenol cotton blue do?

Answer 12

preserves fungal structures, reduce contamination of the environment, and stains the hyaline fungal structures

Question 13

When a systemic mycosis has spread to various organs, what term is used to describe it?

Answer 13

disseminated

Question 14

What organism is best described as a thick-walled yeast cell with buds attached by a broad base?

Answer 14

Blastomyces

Question 15

Which systemic fungus is always a yeast?

Answer 15

Cryptococcus

Question 16

How is histoplasmosis acquired?

Answer 16

inhalation of spores from a free-living fungus

Question 17

Name the five species of dimorphic (diphasic) fungi

Answer 17

Blastomyces, Histoplasma, Coccidiodes, Paracoccidiodes, Sporothrix

Question 18

Which systemic fungus produces thick-walled yeast cells with multiple buds in tissue?

Answer 18

Paracoccidiodes

Question 19

Which fungus can be observed as a non-budding, thick-walled spherule containing endospores in a direct smear from the body?

Answer 19

Coccidiodes

Question 20

Which fungus produces spiny, tuberculate macroconidia when cultured, but in the body can be seen as intracellular, yeast-like cells with a large vacuole in the cells of the RE system?

Answer 20

Histoplasma

Question 21

Cryptococcosis is usually seen as a disease of which body system?

Answer 21

pulmonary

Question 22

Which systemic fungus is the most fastidious in the laboratory?

Answer 22

Histoplasma

Question 23

What systemic fungus causes San Jacquain Valley Fever?

Answer 23

Coccidiodes

Question 24

Which systemic fungus causes South American blastomycoses?

Answer 24

Paracoccidiodes

Question 25

Which stain is best to use to demonstrate Cryptococcus neoformans in CSF?

Answer 25

India ink

Question 26

Which systemic fungus is endemic in Piedmont, NC and can produce a primary pulmonary infection or a primary skin infection which resembles ringworm?

Answer 26

Blastomyces

Question 27

Which systemic fungus produces chains of arthrospores and can be confused with the saprophytic fungus Geotrichum candidum?

Answer 27

Coccidiodes

Question 28

What is the macroscopic appearance of Sporothrix scheneckii at 37C?

Answer 28

Creamy, yeast colony

Question 29

List several species of dematiaceous fungi?

Answer 29

Cladosporium, Phialophora, Fonsecaea

Question 30

Which subcutaneous infection produces yeast-like brown cells in clusters in the body?

Answer 30

Chromomycoses; divides in all four planes; brown, sclerotic bodies

Question 31

What is the most common cause of maduromycosis?

Answer 31

Petriellidium boydii

Question 32

What color are the granules that are frequently found in the pus?

Answer 32

yellow to whitish granules

Question 33

What fungus produces tear-shaped condo arranged in rosettes at 25C and yeast cells when grown at 37C and causes a disease common among gardeners which is referred to as "rose fever"?

Answer 33

Sporothrix schenkii

Question 34

Name several species that can be responsible for chromomycosis.

Answer 34

Phialophora, Fonsecaea, Chlamydosporium

Question 35

Which organisms can cause mycetomas?

Answer 35

Actinomyces, Madurella, Petriellidieum

Question 36

An organism which produces brown, branching septet hyphae would be classified as what type of fungus?

Answer 36

Dematiaceous

Question 37

What are dermatophytes?

Answer 37

organism that only invades keratinized areas (hair, skin, and nails)

Question 38

What device can be used as an aid to select hairs infected with ringworm?

Answer 38

Fluorescent light

Question 39

What type of hair infection is characterized by empty areas or tunnels where the hyphae have degenerated visible throughout the entire length of the hair?

Answer 39

Favic

Question 40

What combination of fungal media would be best to use to culture dermatophytes?

Answer 40

Sabouraud's and mycosel

Question 41

Which three genera of fungi all cause ringworm of the skin?

Answer 41

Microsporum, Trichophyton, Epidermophyton

Question 42

What fungus appears velvety white on the front and mahogany on the reverse and will not grow on sterile unfortified rice grains?

Answer 42

Microsporum audouinii

Question 43

What fungus is the most common cause of ringworm in dogs and cats and is characterized by a canary yellow reverse and spiny, spindle-shaped macroconidia?

Answer 43

Microsporum canis

Question 44

What fungus is most frequently isolated from human ringworm infections and has a deep red reverse pigmentation?

Answer 44

Trichophyton rubrum

Question 45

What structures are frequently observed in Trichophyton cultures?

Answer 45

spiraled/coiled hyphae, nodular bodies, racket hyphae

Question 46

As a rule, which dermatophyte does not infect nails?

Answer 46

Microsporum audouinii

Question 47

Which dermatophyte is the most common cause of epidemic scalp ringworm in American school children?

Answer 47

Trichophyton tonsurans

Question 48

What fungus causes tinea versicolor?

Answer 48

Pityrosporon furfur

Question 49

What fungus is the most common causative agent tinea cruris?

Answer 49

Epidermophyton flacosum

Question 50

What term is used to refer to ringworm of the skin?

Answer 50

Tinea corprus

Question 51

What dermatophyte gives a positive in vitro hair test?

Answer 51

Trichophyton mentagrophytes

Question 52

Which dermatophyte produces sterile, antler-like hyphae referred to as a favic chandeliers and causes a severe type of ringworm of the scalp called favus?

Answer 52

Trichophyton schoenleinii

Question 53

Which dermatophyte does not invade hair and produces oval, smooth-walled club-shaped macroconidia and no microconidia?

Answer 53

Epidermophyton floccosum

Question 54

Which dermatophyte is the most common cause of ringworm of cattle and requires both inositol and thiamine to grow well?

Answer 54

Trichophyton verrucosum

Question 55

How is Candida albicans identified?

Answer 55

germ tube and chlamydospore agar

Question 56

Which fungus is the most common and troublesome laboratory contaminant and is the most pathogenic of the opportunistic fungi?

Answer 56

Aspergillus

Question 57

If an autopsy revealed systemic infection by fungus with broad, branching non-septate hyphae, which species of fungus could be a likely cause of death?

Answer 57

Mucor or Rhizopus

Question 58

Which fungus commonly produces oval budding cells with pseudohyphae and will produce chlamydospore on cornmeal agar?

Answer 58

Candida albicans

Question 59

Brown gritty deposits in a sputum specimen are indicative of what genus?

Answer 59

Aspergillus

Question 60

What clinical conditions can be caused by Candida albicans?

Answer 60

yeast infection, thrust, monilia etc

Question 61

Which species of opportunistic fungi can be causative agents of eye infections?

Answer 61

Altenaria

Question 62

Which fungus is most frequently isolated in the clinical laboratory?

Answer 62

Candida albicans

Question 63

Which species of Rickettsia causes epidemic typhus?

Answer 63

Rickettsia prowazekii

Question 64

Which species of Rickettsia causes scrub typhus?

Answer 64

Rickettsia tsutsugamuschi

Question 65

Which species of Rickettsia causes Q fever?

Answer 65

Coxiella burnetti

Question 66

Which species of Rickettsia causes Rickettsial pox?

Answer 66

Rickettsia akari

Question 67

Which species of Rickettsia causes RMSF?

Answer 67

Rickettsia rickettsii

Question 68

How do Rickettsia and Chlamydia differ?

Answer 68

Rickettsia requires arthropod vectors

Question 69

What clinical conditions can be caused by Chlamydia trachomatis?

Answer 69

Most common cause of non-gonococcal urethritis (NGU) and blindness inclusion conjunctivitis

Question 70

How is psittacosis spread to humans?

Answer 70

Aerosol/inhalation, exposure to infected birds

Question 71

How are Rickettsial infections diagnosed in the laboratory?

Answer 71

cell culture to embryonated eggs

Question 72

What causes the rash that is frequently observed in Rickettsial infections?

Answer 72

invasion of endothelial cells of blood vessels

Question 73

What are the characteristics of viruses?

Answer 73

have DNA or RNA; don't respond to antibiotics; obligate intracellular parasite

Question 74

What term is used to refer to the viral nucleic acid core together with its protein coat?

Answer 74

nucleocapsid

Question 75

What is the order of events in the process of viral infection?

Answer 75

absorption, penetration (viropexis), replicate, assemble, release

Question 76

What is interferon?

Answer 76

prevents viral replicaiton

Question 77

Which virus produces an acute respiratory infection and is commonly found in increased incidence in military camps?

Answer 77

Adenovirus

Question 78

Which virus is the causative agent of the common cold?

Answer 78

Rhinovirus

Question 79

Which type of virus is referred to as "virus in search of a disease"?

Answer 79

ECHO virus

Question 80

What does ECHO stand for?

Answer 80

enteric cytopathogenic human orphan

Question 81

Neri bodies are characteristic of which virus?

Answer 81

Rhabdovirus (rabies)

Question 82

Which virus causes chicken pox?

Answer 82

Varicella

Question 83

With what clinical conditions is Epstein-Barr virus associated?

Answer 83

Burkitt's lymphoma and infectious mononucleosis. transforms lymphocytes to lymphoblastoid cells

Question 84

Which virus produces large, red intracellular inclusions?

Answer 84

CMV

Question 85

How is Hepatitis A transmitted?

Answer 85

oral-fecal

Question 86

Herpes-Zoster occurs in patients who have a history of what other viral infection?

Answer 86

chicken pox

Question 87

What are the characteristic of Hepatitis B?

Answer 87

Transmitted by blood (serum hepatitis), drug addicts (blood contact)

Question 88

How many serotypes of polio virus are there?

Answer 88

3

Question 89

Which vaccines have been developed against polio?

Answer 89

Salk and Sabin vaccines

Question 90

Which virus has been associated with cancer of the cervix and causes genital lesions in humans?

Answer 90

HSV type II

Question 91

What is the serological test used in the identification of Rickettsia?

Answer 91

Wiel-Felix test

Question 92

The Wiel-Felix test employs three antigens that cross-react with rickettsial antigens from what bacteria?

Answer 92

Proteus vulgaris

Question 93

What virus is associated with severe congenital abnormalities in the fetus if the mother becomes infected during her first trimester?

Answer 93

Rubella (German measles)

Question 94

What emerging viral pathogen causes an upper respiratory tract infection in infants and young children?

Answer 94

RSV

Question 95

What does RSV stand for?

Answer 95

respiratory syncytical virus

Question 96

To what group of viruses does HIV belong?

Answer 96

retrovirus

Question 97

What is the enzyme in retrovirus that is capable of converting RNA to DNA?

Answer 97

reverse transcriptase

Question 98

Disease processes that are common in HIV patients that are rarely seen in "normal" individuals

Answer 98

PCP pneumonia, toxoplasmosis, CMV, Kaposi's sarcoma, Cryptococciosis, MAI tuberculosis

Question 99

What vector is responsible for transmitting Rickettsia akari?

Answer 99

mite

Question 100

What vector is responsible for transmitting Rickettsia prowazekii?

Answer 100

body louse

Question 101

What vector is responsible for transmitting Rickettsia rickettsii?

Answer 101

wood tick

Question 102

What vector is responsible for transmitting Rickettsia tsutsugamuschi?

Answer 102

larval mite

Question 103

What vector is responsible for transmitting Rickettsia typhi?

Answer 103

rat flea