Fungi Part 2

Question 1

How are molds identified in lab?

Answer 1

1. Molds identified regardless of source
2. Molds that fail to sporulate may be reported but not identified if dimorphism has been ruled out
3. based on macroscopic and microscopic morphology.

Question 2

What are some safety measures taken working with fungus cultures and specimens?

Answer 2

1. All mold work are done in Class II bio safety cabinets
2. Plates sealed at all times using shrink seal except in lvl 2 bio safety cabinets
3. Yeasts can e handled on. Benchtops

Question 3

What are the three criteria’s mold identification is based on?

Answer 3

Growth rate, colonial morphology, and microscopic morphology

Question 4

What are the preparations for microscopic observation?

Answer 4

1. tape preparation
2. Wet mount (tease prep)
3. Micro slide culture
4. Lactophenol cotton

Question 5

Fungi cultivation are usually at what temperature?

Answer 5

Room temperature unless you are looking for yeast phase

Question 6

What are common media used for fungi culture?

Answer 6

Sabouraud dextrose, potato flake, BHI, and mycosel (cycloheximide)

Question 7

What are differential media used for fungi culture?

Answer 7

Cottonseed conversion, urea, and trichophyton agar 1-7 and corn meal agar

Question 8

Penicillium under the microscope?

Answer 8

Are finger bone like

Question 9

Aspergillus under the microscope looks like?

Answer 9

A fan, peacock’s feather tail or the tesla’s plasma ball

Question 10

Aspergillus fumigatus colony in plate looks like

Answer 10

Green round colonies

Question 11

Aspergillus niger under the microscope and on a culture plate looks like?

Answer 11

Niger = Black
Microscopy - Black fan like structure or a black dandelion
Culture plate - Round colony with white edge and black center

Question 12

Aspergillus flavus on plate and microscope?

Answer 12

Plate - Round colony, alternating blue and white with some spotting.
Microscope - Blue color with fan like structure connected to septated hyphae

Question 13

What does alternaria look like on a plate and microscope?

Answer 13

Plate - Black colony with black edge. May have an irregular round shape.
Microscope - Brown segmented ellipse attached to hyphae

Question 14

Dermatophyte on a plate and microscope?

Answer 14

Plate - Colones are round with smooth edge or fine edge. The color can be white or dark brown
Microscope?