Mycology Flashcards
What are the biological significances of fungi
are non-photosynthetic eukaryotic heterotrophs
- decomposes of organic tissues
What is saprotropism
Decomposition of organic tissues
What is fungi’s roles as pathogens ( esp. Of plants )
Dutch elms disease
What is fungi’s role as symbionts
Mycorrhizae associated with plant roots
When was the first fossil record of fungi dated to
540 million years ago
What was fungi’s ancestor
A flagellated protist.
What are somebiological characteristics of fungi
Eukaryotic
Multicellular ( yeast is unicellular)
Fungal tissue is composed of hyphae
What are the 2 types of hyphae and what is each one
septate hyphae - septae divide hyphae into cells with separate nuclei, organelles etc.
aseptate hyphae - no separate cells in cytoplasm (coenocytic) with many nuclei,
organelles
What is the mycelium
The entire hyphal mass
What are some factors of aseptate fungi
Not partitioned into smaller cells
They’re multinucleate
They’re coenocytic
What are some factors of septate fungi
They contain septa (Cross walls dividing cells of mycelium)
Each cell has 1 or 2 nuclei
Nuclear division followed by cross-wall formation
What is apical growth
The process by which hyphae extend
Is the inside or outside of the hyphae stronger
Inside
What processes occur at the apical tip.
Apical vesicles are produced from Golgi bodies and transported to
the tip by elements of the cytoskeleton - probably microtubules or
actin microfilaments
• Cell wall at extreme apex is structurally weak, continuous arrival of
vesicles containing enzymes for wall synthesis/ lysis, polymers
and polymer components
What is the splitzenkorper
An accumulation of small, membranebound vesicles of different sizes and content surrounding a central vesicle free core
What are the classification groups in nomenclature
Kingdom, phylum, subphylum, class, order, family, genus, specific epithet, sub species (strain)
What are the 8 phyla of the fungal kingdom
- Ascomycota
- Basidiomycota
- Mucoromycota
- Zoopagomycota
- Neocallimastigoycota
- Chytridiomycota
- Blastocladiomycota
- Cryptomycota
Define Zygomycota ( outdated fungal classification)
aseptate, sexual and asexual reproduction. Redefined across the new phyla
Define Glomeromycota ( outdated fungal classification)
. aseptate, asexual reproduction only. Redefined across the new phyla
Define Deuteromycota ( outdated fungal classification)
again reclassified into the new fungal phyla or as
organisms called oomycota [oomycetes]
What are the factors + figures of ascomycota
• One of the two largest fungal phyla
• Approximately 2000 genera and 30,000 species identified
• Constituted of filamentous fungi and yeasts.
• Some used in commercial and medical processes
• Some disease causing and human pathogens most commonly in this phyla
• Characterised by the production of spores in an ascus (pl. asci) during
sexual cycle
• Include the yeasts (eg. Saccharomyces spp., Candida spp.), most lichen-
forming fungi
What are the factors + figures of Basidiomycota
One of the two largest fungal phyla
• Approximately 1,600 identified genera and 32,000 species
• Sexual reproduction is the most prominent mode of propagation, rarely asexual via conidia
• Reproduction through the production of a basidiocarp and basidiospores
What are the factors + figures of Chytridiomycota
About 700 species
• Aseptate mycelium
• In some cases hyphae branch to form root-like rhizoids in the
food source
• Sexual spores are flagellate - often classified as protists in the
past
• Predominantly haploid, short dikaryotic and diploid phases in
sexual cycle
• Cell wall composed of Chitin
• Moist terrestrial habitats, such as forest litter layer, or in
freshwater, some marine usually forming molds on dead tissue
What are the 3 fungal reproductive methods
Asexual, sexual, parasexual
How do fungal cells asexually reproduce
nuclei of somatic cells divide by constriction or (more usually) mitosis
• Daughter cells liberated (spores)
What’s an example of a fungi that asexually reproduces
ascomycota
How do fungal cells asexually reproduce
fusion of two n nuclei as in other organisms
• usually followed by meiosis to form haploid hyphal cells … liberation of haploid spores
What’s an example of a fungi that sexually reproduces
Ascomycota
What is parasexual reproduction and how does it work in fungi
Mycelium becomes heterokaryotic by anastomosis (fusion of different
hyphae)
-this usually gives rise to a dikaryotic phase
• Some n nuclei within a mycelium can fuse to form 2n nuclei, these then
divide mitotically, along with remaining n nuclei, in the same
mycelium.
• Incomplete mitosis leads to haploidisation (n) [reduction division back
to haploid state, due to sequential loss of chromosomes
What types of fungi are pathogenic to humans
Aspergillus fumigatus, Candida albicans
Is genetic material exchanged between sexual or asexual reproduction in fungi?
Sexual
