a. Class Phycomycetes. The algal fungi: bread molds and leaf molds. The
only known mycosis (fungal disease) caused by fungi of this class is mucormycosIs, a
very rare fungal growth of the upper respiratory tract, bronchial mucosa, and lungs. It
occurs largely as a complication of a chronic, debilitating disease, such as uncontrolled
diabetes.
b. Class Ascomycetes. The sac fungi: yeasts, mildews, and cheese molds.
Fungi of this class are implicated in only three fungus diseases, all of which are rare.
c. Class Basidiomycetes. Mushrooms, toadstools, rusts, and smuts. The only
pathogens in this class are the mushrooms of the genus Amanita, which cause severe
systemic poisoning (sometimes death) when eaten.
d. Class Deuteromyceters. Fungi imperfecti: a heterogeneous collection of
fungi without sexual reproduction. Most of the pathogens encountered in medical
mycology belong to this class.
Character-
Origin of
Examples of
Patho-
Taxonomic
Hypha
Type
istic
Spore
Fungi
genicity
class of
of
spore
Fungi
Repro-
duction
Phycomycetes
Asptate
Asexually
Sporangio-
Sporangio
Nuisance fungi
Very rare
spore
phore
including
Mucormycosis
general
Sexually
Zygospore
Fussion of
Absidia,
or
nuclei
Muclor, and
oospore
Rhizopus
Ascomycetes
Septate
Asexually
Blastospore
Budding
Allescheria
Rare
Aspergillus
Maduromcosis
Conidium
Conidio-
Piedraia
Aspergillosis
phore
Black Piedra
Sexually
Ascospore
Ascus
Saccharomyces
(perfect yeast)
Basidiomycete
Septate
Sexually
Basidio-
Basidium
Mushrooms,
Rare
s
spore
smuts and
Mushroom
rusts
poisoning
Deutero-
Septate
Asexually
Thallospore
Thallus
Most
Most Mycoses
mycetes
(hypha)
saprophytes
encountered
{fungi
and pathogens
in medical
imperfecti)
Conidium
encountered
mycology
Conidio-
in medical
phore
mycology
(Imperfect
mold and
yeast)
Table 2-5.
Characteristics of Fungi.
MD0151
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