Microbiology - Fungi

Question 0

Multicellular colonies composed of clumps of intertwined branching hyphae?

Answer 0

Molds/Mycelia

Question 1

Unicellular growth form of fungi?

Answer 1

Yeast

Question 2

Hyphae?

Answer 2

Treadlike, cylindrical, tubules composed of fungal cells attached end to end.

Question 3

Spores?

Answer 3

The reproducing bodies of molds.

Question 4

Saprophytes?

Answer 4

Fungi that utilize organic matter(soil, rotten vegetation) as an energy source.

Question 5

The essential sterol in fungi?

Answer 5

Ergosterol.

Question 6

Fungal cell wall?

Answer 6

surrounding the cell membrane, composed mainly of carbohydrates with some proteins.

Question 7

Fungal capsule?

Answer 7

Polysaccharide coating that surrounds the cell wall.

Question 8

Pityriasis versicolor?

Answer 8

chronic superficial fungal infection that leads to hypo- or hyperpigmented patches on the skin.

Question 9

Tinea nigra?

Answer 9

Superficial fungal infection that causes dark brown to black painless patches.

Question 10

What causes Pityriasis versicolor?

Answer 10

Malassezia furfur

Question 11

Three common dermatophytes?

Answer 11

1 Microsporum
2 Trichophyton
3 Epidermophyton

Question 12

Tinea corporis?

Answer 12

Invasion of the horny layer of the skin. Called ring worm.

Question 13

Tinea pedis?

Answer 13

Athlete’s foot.

Question 14

Tinea unguium?

Answer 14

The nails are thickened, discolored and brittle.

Question 15

Three manifestations of Candida albicans?

Answer 15

Mouth - oral trush
Groin - diaper rash
Vagina - candida vaginitis

Question 16

Sporotrichosis, spread and manifestations?

Answer 16

The infection spreads along lymphatics to local nodes. Presents as nodules. This nodule ulcerates and become necrotic. As it heals, new ulcers pop up along the lymphatic tracts.

Question 17

Three fungi that cause systemic disease?

Answer 17

1 Histoplasma capsulatum(uncapsulated)
2 Blastomyces dermatidis
3 Coccioides immitis

Question 18

Compare Histoplasma, Blastomyces and Coccidioides with tuberculosis

Answer 18

Like tuberculosis:

Inhaled, primary infection in the lung.
Asymptomatic, mild, severe or chronic lung infection.
Lung granulomas, calcifications and/or cavitations.
Can disseminate hematogenously to distant sites.

Question 19

3/4 of cryptococcus neoformans occur in?

Answer 19

Immunocompromised persons.

Question 20

What two forms of Candidiasis manifest in immunocompromised, but not in immunocompetent people?

Answer 20

Esophagitis - Extension of oral trush cause substernal pain. Never seen in the immunocompetent!

Disseminated - invade the blood stream and from there any organ. Candida albicans is part of normal flora, but isolation from blood is never normal.

Question 21

Three major diseases caused by Aspergillus fumigatus?

Answer 21

1 Allergic Bronchopulmonary Aspergillosis
2 Aspergilloma - lung cavities
3 invasive aspergillosis - invasive infection of lung

Question 22

Toxin produced by Aspergillosis?

Answer 22

Aflatoxin

Question 23

Common cancer in subsaharan africa that’s related to aspergillosis?

Answer 23

Half of the cancers south of the sahara desert are liver cancers and 40% of screened foods contain aflatoxins.

Question 24

Three primary pathogens of Mucormycosis?

Answer 24

1 Rhizopus
2 Rhizomucor
3 Mucor

Question 25

Name two fungi-like bacteria?

Answer 25

Actinomycetes and Nocardia frequently grow as mold and are soil and water saprophytes. Still, both are truly bacteria.