Fungi: A- Exam IV Flashcards
What are three main characteristics of fungi?
- Eukaryotes
- Spore-forming
- No chlorophyll
List the oxygen requirements of fungi:
most are aerobic, some facultative and strict anaerobes
The cell wall of fungi usually contains:
chitin
polysaccharide containing N-acetyl glucosamine (NAG)
chitin
What are the two growth forms of fungi?
- filamentous (molds)
- unicellular (yeasts)
Filamentous fungi (molds), have threadlike filaments called:
hyphae
Mass of hyphae:
mycelium
What are the two categories of hyphae found in filamentous fungi?
septate vs. coenocytic
Septate vs. coenocytic hyphae describe:
the crosswalls
Filamentous fungi grow by:
extension of tip and branching
Describe the cells of unicellular fungi (yeasts):
single ovoid or spherical cells
How do unicellular fungi (yeasts) reproduce?
asexually by cell division (budding) or sexually by cell fusion and spore formation
Asexual reproduction of fungi can be by:
cell division (budding) (transverse division), or spore formation
Some yeast-forms of fungi perform asexual cell division by ____, others by ___.
budding; transverse division (fission)
sexual reproduction of fungi involves production of:
sexual spores
sexual reproduction of fungi involves production of sexual spores by:
meiosis of a diploid cell
Form producing asexual spores, often mold-like growth form:
anamorph
Form producing sexual spores, typically a fruiting body:
teleomorph
ability to grow as yeast form or mold form:
dimorphism
Many pathogenic fungi are:
dimorphic
Although many pathogenic fungi are dimorphic, ___ form more typical at human body temp
What is an exception to this? Why?
yeast
candida; both forms of candida exist inside and outside the body
Both forms of ____ exist inside and outside the body
candida
Candida forms ___ & ___
psuedohyphae & pseydomycelia
Hyphal growth is a modified budding where newly budded cells remain attached to mother cell
psuedohyphae
Some pathogenic fungi such as aspergillum and cryptococcus neoformans are not:
dimorphic
A pathogenic fungi that is not dimorphic as it exists in mold form only:
aspergillus
A pathogenic fungi that is not dimorphic as it exists in yeast form only:
cryptococcus neoformans
Diseases caused by fungus or mold:
mycoses
Fungal infections are classified by affected area of body such as:
- superficial
- cutaneous
- subcutaneous
- systemic
The primary mechanisms for the human body to fight fungi:
- neutrophil phagocytosis and killing
- T-cell mediated immunity
Fungal infections of keratinized outer layers of skin, hair, and nails:
superficial mycoses
Superficial mycoses are typically ___ with ___
mild infections with minimal inflammatory repsonse
Describe the treatment for superficial mycoses:
easy to treat or clears without treatment
Fungal infections of the hair shaft:
piedras
Give an example of a piedra:
trichosporon beigelii
Trichosporon beigelli may also be referred to as:
shite peidra
Fungal infections involving outer layer of skins, hair, and nails:
tineas
Give examples of a tinea infection:
Malassezia furfur
Malassezia furfur may also be referred to as:
pityriasis versicolor
Most tineas and piedras occur in the:
tropics
What are the most common superficial mycoses?
- pityriasis versicolor
- white piedra
What type of disease is pityriasis versicolor?
tinea