Mycology Introduction Flashcards
How many species of fungi exist? How many have been described?
1.5 million species, > 80,000 species described
How many species of fungi are considered to be pathogenic to humans and animals?
400 species pathogenic for humans and animals
Are Fungi eukaryotic or prokaryotic?
Eukaryotic
Fungi are non-___________, ______trophs, produce _____enzymes, and obtain nutrients by ________.
photosynthetic, hetero, exo, absorption
What is fungal classification based on ?
Morphology, physiology, the presence of
macromolecules and sexual mating.
The form of a fungal species during its sexual reproductive life cycle is termed ______________. Its asexual form is referred as _________.
teleomorph, anamorph
Fungi reproduction by _____ formation may be either _____ or ______.
spore, sexual, asexual
What is the term for fungi that lack a meiotic stage ?
Mitosporic fungi.
Fungal species may be ?
saprophytic, parasitic or mutualistic.
Fungi are _______ distributed in the environment.
widely
Fungi cell walls contain?
Chitin and other polysaccharides
What are the two major forms of fungi?
Branching hyphae and unicellular yeasts.
Fungi grow ________ at 25 degrees celsius . Some moulds are _________ ________.
aerobically, strict aerobes
Fungi tolerate ______ osmotic pressures and _____ pH values. Grow on _________ _________ agar, pH ____.
high, low, Sabouraud, dextrose, 5.5
Fungi are resistant to ________ drugs which are effective against bacteria.
antimicrobial
The majority of fungi are _________, some cause _________ infections.
saphrophytes, opportunistic
Dermatophytes are pathogens that cause ____________ in animals and humans.
ringworm
Name the three Fungal phyla that are of veterinary importance.
Fungi of veterinary importance are found in the three phyla: Ascomycota , Basidiomycota and Zygomycota
The two main morphological fungal forms of fungi are _______ and ______.
moulds, yeasts
Moulds grow as __________ filaments called ______ (A), whereas the unicellular yeasts have an ______ or _____ appearance (B)
branching, hyphae, oval, spherical
What can be seen in this image?
The two main morphological fungal forms are moulds and yeasts.
Moulds grow as branching filaments called hyphae (A), whereas the
unicellular yeasts have an oval or spherical appearance (B)
Dimorphic fungi occur in both ______ and _______ forms
mould, yeast
Fungi such as Candida albicans , which produce forms additional to
the two major forms, are described as _________.
polymorphic
Hyphal cell walls, are mainly composed of __________ components including chitin macromolecules with _________ cross - linkages.
In yeasts, cell walls contain _____ complexed with ______ and, in some species, a range of ______ compounds. In the bilayered cell
membrane contains ________.
carbohydrate, cellulose, protein, polysaccharides, lipid, cholesterol
Both moulds and yeasts have ______ with well defined nuclear ________, _____________ and networks of _____________.
nuclei, membranes, mitochondria, microtubules
What can be seen in the image below?
Stages in the germination of a fungal spore leading
to the development of a branched hyphae.
What can be seen in the image below?
Septate hyphae
What can be seen in the image below?
Aseptate hyphae
What can be seen in the image below?
Describe the growth, reproduction, and colonial formation of Fungi.
Label the image below accordingly
What can be seen in the image below?
What can be seen in the image below?
What can be seen in the image below?
What can be seen in the image below?
What can be seen in the image below?x
What can be seen in the image below?
Describe the textures seen below.
How would you describe these three fungal topography?
How would you describe the diagnostic structures of these fungi?
List the Factors which may predispose to fungal invasion of tissues.
- Immunosuppression
- Prolonged antibiotic therapy
- Immunological defects
- Immaturity, ageing and malnutrition
- Exposure to heavy challenge of fungal spores
- Traumatized tissues
- Persistent moisture on skin surface
- Some neoplastic conditions
List the mechanisms involved in fungal diseases.
- Tissue invasion (mycosis)
- Toxin production (mycotoxicosis)
- Induction of hypersensitivity
Where would you typically find lesions in an animal suffering from Superficial mycoses?
What is this classified as?
Where would you typically find lesions in an animal suffering from subcutaneous mycoses?
What is this classified as?
Where would you typically find lesions in an animal suffering from systemic mycoses?
What is this classified as?
How do you diagnose fungal infections?
- Clinical signs and history of the disease
- Samples: hair, skin, biopsies (Periodic acid-Schiff, methanamine silver impregnation)
- Direct microscope observation –> wet preparation (10% KOH)
Spore –> lactophenol cotton blue - Mycological culture –> Sabouraud dextrose agar (SDA)27-37°C
Adiaspores are spores that ________ in size without replication.
increase
Aerial hyphae are _____ the agar surface. They often produce _____ structures.
above, fruiting
Anamorph fungi are an ________ form of fungus.
asexual
Anthropophilic describes fungi that usually infect?
Humans only
Apical fungi are located at the ______ of a pointed extremity.
tip
Arthrospore (arthroconidium) is an _____ spore formed by the fragmentation of a hypha. The resulting spores can be ?
asexual, rectangular, barrel-shaped, or can become rounded.
Asocarp is a ______ sac within which are formed _____ and ______ of the ascomycetes.
mycelial, asci, ascospores
Ascospores are the ______ spores of the ascomycetes, which develop in a sac-like structure termed an _____.
sexual, ascus
