Lab Exam 1

Question 1

What part of the body does tinea ungium affect?

Answer 1

nails

Question 2

What part of the body does tinea corprus affect?

Answer 2

body

Question 3

What part of the body does tinea pedis affect?

Answer 3

foot

Question 4

What part of the body does tinea barbay affect?

Answer 4

beard

Question 5

What part of the body does tinea cruris affect?

Answer 5

groin

Question 6

What part of the body does tinea capitis affect?

Answer 6

scalp

Question 7

What does the word “tinea” mean?

Answer 7

ringworm

Question 8

What is the short lateral structure that will develop when certain yeast are incubated at 37C in a rich medium?

Answer 8

germ tube

Question 9

What is one yeast that is germ tube positive?

Answer 9

Candida albicans

Question 10

At what temperature should chlamydospore agar be incubated?

Answer 10

25C or room temperature

Question 11

Where should the technologist look for spores on a chlamydospore agar plate?

Answer 11

on the edge of the cover slip

Question 12

What color and shape are the spores on a chlamydospore agar plate?

Answer 12

blue and round

Question 13

What is the principle of the India ink preparation?

Answer 13

India ink particles bounce off the capsule so that you can see a clear halo of the organism under high power

Question 14

What organism is India ink especially used for?

Answer 14

Cryptococcus neoformans

Question 15

What type of specimen is most frequently used in an India ink prep?

Answer 15

spinal fluid

Question 16

What reagent should be used for the examination of the reproductive structures of molds that are already growing in a culture?

Answer 16

lactophenol cotton blue

Question 17

What technique can be used to “save” wet preps for future use?

Answer 17

clear fingernail polish around the edge of the coverslip to keep it moist

Question 18

Name several media used for the primary isolation of fungi.

Answer 18

Sabs, SabsC, BHI, SDA, mycosel, mycobiotic

Question 19

Why would you incubate a culture for fungi at 25 and 37?

Answer 19

fungus is dimorphic; grows as a mold at 25C and a yeast at 37C

Question 20

What term is used for fungi that grow differently at 25 and 37?

Answer 20

dimorphic or diphasic

Question 21

Why do mycologists use KOH?

Answer 21

used on a specimen directly from the body because it will dissolve the keratin material of the skin, hair, or nails

Question 22

What specific protein does KOH affect?

Answer 22

keratin

Question 23

Name some fungal elements that could be seen in a KOH prep.

Answer 23

hyphae, pseudohyphae, blastospres, arthrospores, budding yeast

Question 24

What does ectothrix hair invasion mean?

Answer 24

invasion outside of the hair shaft

Question 25

What does endothrix hair invasion mean?

Answer 25

invasion inside the hair shaft

Question 26

Name some genus of fungus which cause ringworm.

Answer 26

Microsporum, Epidermophyton, and Trichophyton

Question 27

Name some genus of fungus which exhibit dimorphism

Answer 27

Blastomyces, Coccidioides, Histoplasma, Sporothrix, and Paracoccidioides

Question 28

Name some genus of fungus that is a frequent contaminant.

Answer 28

Aspergillus and Penicillium

Question 29

What is a slide culture?

Answer 29

piece of agar is inoculated on four corners then a coverslip is placed on it and incubated.

Question 30

What is the best way to observe fungal cultures in their natural morphology?

Answer 30

slide culture

Question 31

Answer 31

Mucor

Question 32

Answer 32

Penicillium

Question 33

Answer 33

Cladosporium

Question 34

Answer 34

Aspergillus

Question 35

Answer 35

Microsporum

Question 36

Answer 36

Trichophyton