Laboratory Practical

Question 1

Purpose of KOH preparation

Answer 1

A 10% potassium hydroxide (KOH) preparation is used when specimens such as hair, nails, skin or tissue are to be examined for fungal elements.
KOH digests the host cellular material allowing the fungal elements to be more easily seen.

Question 2

Purpose of India Ink Procedure

Answer 2

When combined with pelleted material from cerebrospinal fluid, India ink allows visualization of the polysaccharide capsules of the yeast, Cryptococcus neoformans.

Question 3

Purpose of lactophenol stain for a fungal wet mount

Answer 3

Used to enhance the hyphial and reproductive structures of molds.

Question 4

Sabouraud Dextrose Media

Answer 4

Supports most saprophytic fungi and pathogenic molds, non-inhibitory. 2% glucose with a neutral pH.

Question 5

Inhibitory mold agar

Answer 5

Inhibits most bacterial growth, the antibiotics typically included are chloramphenicol and possibly gentamicin, penicillin, ciprofloxacin, and streptomycin.

Question 6

Brain heart infusion agar

Answer 6

And enriched media made from infusions of calf brain and beef heart, usually used for recovery of dimorphic molds, this media may have sheep blood added; antibacterial additives are also available.

Question 7

Mycocel/Mycobiotic Agar

Answer 7

Contains cycloheximide and chloramphenicol to inhibit most saprophytic molds, can also inhibit Candida, Cryptococcus, zygomycetes and other potentially significant molds useful for Dermatophyte recovery

Question 8

Chromagar Candida

Answer 8

Uses variations of vitamin content to differentiate mixed yeast cultures

Question 9

Media for sporulation

Answer 9

Corn meal with tween 80, Trypan blue or dextrose, potato dextrose, potato flake, brain heart infusion with sheep blood, water agar, Hay agar, oatmeal agar, V-8 agar, and carnation leaf agar

Question 10

Biochemical media

Answer 10

Germ tube, trichophyton agar, API strips, birdseed agar, urea, nitrate agar

Question 11

Hyaline hyphae

Answer 11

Clear, transparent, or lightly pigmented

Question 12

Dematiaceous Hyphae

Answer 12

Dark hyphae and conidia that may appear black or brown due to melanotic pigment the cell wall

Question 13

Septate

Answer 13

Having cross walls in hyphae, conidia or spores without pinching

Question 14

Non-septate hyphae

Answer 14

Hyphae that or a continuous tube without breaks

Question 15

Description of mold texture

Answer 15

Cottony, folded, velvety, granular, smooth, waxy, creamy

Question 16

Arthrospore/Arthroconidia

Answer 16

An asexual spore formed by the breaking up of hyphae at the point of septation, the resulting cell maybe rectangular or barrel shaped with thick or thin walls

Question 17

Blastospore

Answer 17

A conidium formed by budding along a hyphae, pseudohyphae, or a single mother yeast cell

Question 18

Sporangiospores

Answer 18

And asexual spore formed by the cleavage of sporangium contents these are seen in the zygomycetes

Question 19

Dermatophyte

Answer 19

Produce microconidia and macroconidia

Question 20

Microconidia

Answer 20

Small usually single cell conidia, the smaller of the two cells in fungi that produce both large and small conidia, usually round, pear-shaped, club shaped or ovoid

Question 21

Macroconidia

Answer 21

Large usually segmented into two or more cells, they result from the conversion of an entire hyphal element into a multi celled conidia which can be thick or thin walled, smooth or rough, club or oval-shaped, single or in clusters

Question 22

Chlamydiaconidia

Answer 22

Comparable to bacterial spores