MYCO & VIRULOGY L1 (Prelim- Introduction) Flashcards
What are the general characteristics of a Eukaryotic cell?
- Posses true nucleus
- Nuclear membrane
- Mitochondria
What are the 2 types of fungi?
- Yeast
- Mold
Enumerate at least three characteristics of a fungi
- Chitin in cell wall
- Ergosterol in the cell membrane
- Sexual or asexual reproduction
- Lack chlorophyll
- Lack antibiotic susceptibility
- Saprophytic
General considerations for the identification of Yeasts
- Colonial morphologic features
- Microscopic morphologic features
- Psychologic studies
- Rapid commercial yeast identification tests
Most fungi are __________ that grow best at a _______, although they tolerate a wide pH range
obligate aerobes; neutral pH
IDENTIFY: Single vegetative cells (unicellular). Moist, creamy, opaque or pasty colonies on media
Yeast
Yeast reproduces through?
“budding”
This is the term used to describe the daughter cell in “budding”
Blastoconidium
General considerations for the identification of Molds
- Growth rate
- Colonial morphologic features
- Microscopic morphologic features
IDENTIFY: Filamentous Fungi. It has fluffy, cottony, woolly or powdery colonies
Molds
Most molds have a fuzzy or woolly appearance because of
the?
formation of mycelia
Mycelia are made up of
many long strands of tubelike structures called?
hyphae
Hyphae can be classified as?
Aerial or Vegetative
These mycelia extend above the surface of the colony and
are responsible for the fuzzy appearance
Aerial mycelia
This support the reproductive structures that produce conidia
Aerial mycelia
In many cases, these are used to identify different fungal genera
Conidia
These mycelia extend downward into the medium to absorb nutrients
Vegetative mycelia
Enumerate the three different kinds of septation in a hyphae
- Septate
- Sparsely septate
- Aseptate
Enumerate the four different appearances of a hyphae
- Antler hyphae
- Racquet hyphae
- Spiral hyphae
- Rhizoids
This refers to the frequent cross walls of a hyphae
Septate
This refers to the irregular interval (of cross walls) of a hyphae
Sparsely septate
The absence of cross walls of a hyphae
Aseptate
This elevation is described as furrowed or convoluted
Verrucose
This elevation is described as slightly raised in the center
Umbonate
The elevation furrows (and) radiate out from the center
Rugose
How many days does it take for a slow grower to grow?
11-21 days
How many days does it take for a rapid grower to grow?
5 days or less
How many days does it take for an intermediate grower to grow?
6-10 days
IDENTIFY: This is nonpigmented or lightly pigmented. And sometimes referred to as moniliaceous
Hyaline
IDENTIFY: This is darkly pigmented and melanized. Sometimes referred to as dematiaceous.
Phaeoid
This fungus is easy to isolate, and is tan to yellowish
Yeast
In phaeoid, the pigmentation is caused by?
melanin
This is the characteristic of a fungi that refers to its ability to obtain food by absorbing it from its environment
Saprophytic
TRUE OR FALSE: Pigmentation should be seen with a stain
FALSE. It should be seen without a stain
Its black appearance is brought about by the stain not necessarily by a phaeoid
Gomori methylene
In Fontana-Masson, what is the color of the stain if it is a hyaline
pink to red
In Fontana-Masson, what is the color of the stain if it is a phaeoid?
brown
This texture is described as loose, high aerial mycelium
Cottony
This texture is described as high aerial mycelium that appears slightly matted down
Woolly
This texture is described as dense, powdery, resembling sugar granules
Granular
This texture is described as low aerial mycelium resembling a velvet cloth
Velvety
Mold and yeast phase
Dimorphic fungi
If the fungi are dimorphic, mold grows in what temperature?
25C to 30C
This texture has a smooth surface with no aerial mycelium
Glabrous
Both yeast and mold forms in the same culture
Polymorphic Fungi
If the fungi are dimorphic, yeast grows in what temperature?
35C to 37C
This term refers to asexeual reproduction
Anamorph
If the production of spores is endogenous it is termed as ____________, and if it is exogeneous it is _____________
sporangiospore; conidiophore
IDENTIFY: Large, usually multiseptate, and club- or spindle- shaped
Macroconidia
IDENTIFY: small, unicellular, round elliptical
Microconidia
Asexual reproduction results in the formation of _______ following mitosis
conidia
Asexual reproduction
is carried out by specialized fruiting structures known as _______________. This also contains genetic material
Conidiogenous cell
Two common conidiogenous cells are the:
- Phialides
- Annellides
These are vaselike structures that produce phialoconidia
Phialides
These are ringed structures that produce annelloconidia
Annellides