INTRODUCTION TO MYCOLOGY Flashcards
An extremely diverse group of organisms.
FUNGI
Generally classified as molds or yeasts
FUNGI
Recognized as classic pathogens and environmental saprobes living on nonliving material.
FUNGI
Cause mild infections, trigger allergic reactions ( including asthma), and produces serious life-threatening disease.
FUNGI
common cause of UTI, and commonly found in dead living materials (e.g.fallen tree)
YEASTS
General Characteristics of Fungi
Eukaryotic which includes yeast, moulds and mushrooms
Lack chlorophyll – main difference with plants that conducts photosynthesis ; can’t perform photosynthesis ; some are parasitic
Obligate aerobes; Neutral pH ; no embryonic stage ; development from spores
Require moisture (growth) ; store food in the form of starch
Exception: Apores and Conidia
fungi is eukaryotic which includes ____, _____, _____
yeast, moulds and mushrooms
fungi lack chlorophyll which is main difference with plants that conducts ______ ; cannot perform _______ ; some are ______
photosynthesis ; photosynthesis ; parasitic
fungi have cell wall that contains _____ and _____
chitin and polysaccharides
fungi have nuclei that is ______
very small
fungi are ____ aerobes ; _____ pH ; no _____ stage ; develop from _____
Obligate aerobes; Neutral pH ; no embryonic stage ; development from spores
fungi requires _____ for growth
moisture
fungi store food in the form of _____
starch
fungi require moistures with the exception of
apores and conidia (able to survive in dry condition)
basic element of filamentous fungi with a branched tubular structure, 2-10 um in width.
hypha
the web or mat-like structure of hyphae
mycelium
entirety of the mycelia and is also called the fungal body or colony.
fungal thallus
basic element of the unicellular fungi. Round to oval and 3-10um in diameter.
yeast
fungal species that can develop either the yeast or the mycelium form depending on the environment conditions.
dimorphism
single vegetative cells
yeasts
Smooth, creamy, bacterial-like colony without aerial hyphae
yeasts
Similar macroscopic and microscopic morphologies
yeasts
Identification of yeast is based on _______
biochemical testing
yeasts reproduce by ____ or ____
budding or fission
a process where the parent cell enlarges and a septum (wall forms to separate the conidial cell)
Budding
budding involve maturation of the bud to an independent ____________ (daughter cell)
blastoconidium
fuzzy or wooly appearance because of mycelia.
Molds
made up of hyphae
Mycelia
many long strands of tube-like structure that forms the molds.
Hyphae
hyphae = _____ strand and mycelia = ______ strands
hyphae = single strand
mycelia = many strands
2 types of Mycelia
- Aerial Mycelia
- Vegetative Mycelia
extend above the surface of the colony
Aerial Mycelia
Responsible for the fuzzy appearance
Aerial Mycelia
Support the reproductive structures that produce conidia
Aerial Mycelia
Extend downward into the medium to absorb nutrients.
Vegetative Mycelia
mycelia microscopic appearance
- antler hyphae
- racquet hyphae
- spiral hyphae
- rhizoids
Mycelia:Microscopic Appearance
= swollen, branching tips
Antler Hyphae
Mycelia:Microscopic Appearance
= enlarged, club-shaped areas
Racquet Hyphae
Mycelia:Microscopic Appearance
= tightly coiled
Spiral Hyphae
Mycelia:Microscopic Appearance
= rootlike structures; presence and placement can assist with identification
Rhizoids
show frequent cross-walls occurring perpendicularly to the outer walls of the hyphae.
Septate hyphae
have few cross-walls at irregular intervals
Sparsely septate hyphae
absence of septate.
Aseptate (coenocytic)
- Nonpigmented or lightly pigmented
- Number one that causes pigmentation
Hyaline (moniliaceous) hyphae
- Darkly pigmented because of the presence of melanin in the cell wall
- Appear dark brown or almost black (due to melanin)
Phaeoid (dematiaceous) hyphae
stains to determine hyphal pigmentation
Gomori Methylene Stain
Fontana-Masson Stain
All fungal elements appear black.
Gomori Methelyne Stain
specifically stains melanin
fontana-masson stain
hyphae stains in fontana-masson stain
Hyaline Hyphae: Pink to Red
Phaeoid Hyphae: Brown
- ability of some fungi to exist in two forms (mold or yeast)
- dependent on growth conditions
Dimorphism
Dimorphic Fungi (phases)
- Mold Phase
- Yeast Phase (pherule phase or tissue state)
dimorphic fungi where the organism is grown in (22º to 25º C ) in ambient air conditions
Mold Phase
dimorphic fungi seen in vivo; is grown 37ºC with increased CO2
Yeast Phase (pherule phase or tissue state)
- have both yeast and mold forms in the same culture
- occurs despite growth conditions ( Exophiala spp.)
Polymorphism
in reproduction, fungi can reproduce _____ or _____
asexually (imperfect) or sexually (perfectly)
asexual reproduction (arrow process)
Formation of conidia; Conidia contain all the genetic material necessary to create a new fungal colony
to
Followed by mitosis
to
Spores may be included in the conidia that will travel through air that will stick to moist areas, creating new fungi or mushroom.
_________ contain all the genetic material necessary to create a new fungal colony
conidia