Natural classification of fungi Flashcards
Asexual stages of fungi
Anamorph
Sexual stages of fungi
Teleomorph
a primitive group of microscopic fungi; lack chitin in cell walls during feeding stage – forms
during reproductive stage; live as parasites inside minute aquatic organisms such as diatoms and water molds
Cryptomycota
obligate intracellular spore-forming parasites; used to be classified as protozoa
Microsporidia
oogamous phylum of fungi
Monoblepharidomycota
also known as mitospores, multiply by simply splitting into two. This is a fast and efficient way to increase the population
Asexual Spores
These spores form at the tip or side of a hypha, a thread-like structure in fungi. Blastomyces dermatitidis, a fungus causing the lung disease blastomycosis, reproduces by producing ________
Conidia
are simply the cells of a hypha that have been cut off from each other. Fungi like Trichophyton rubrum, which is responsible for athlete’s foot and ringworm, produce these kind of spores
Arthrospores
These are thick-walled spores that help the fungus survive under very extreme conditions. Candida albicans, which causes thrush, produces ______
Chlamydospores
These spores are formed within a sac-like structure called a sporangium. Rhizopus stolonifer, commonly known as bread mold, undergoes reproduction through _______
Sporangiospores
________ or meiospores, on the other hand, are formed by the fusion of two parent cells. This process contributes to the genetic diversity in the fungal population
Sexual Spores
Formed in sacs called asci, each ascus usually contains eight ________. These are produced by Ascomycetes
Ascospores
These spores are formed on a pedestal-like structure called a basidium. Each basidium produces four ______
Basidiospores
This is a result of fusion of cells from two different
fungal strains.
Zygospores
occur in aquatic environments such as streams, ponds, estuaries and marine systems, living as parasites of algae and planktonic organisms.
Chytrids
The only fungi with flagella
Chytrids
________ chytrids are those that consist of a sporangium and filamentous rhizoids
Eucarpic
_______ chytrids that produce thalli that are entirely converted to sporangia during reproduction
Holocarpic
thallus produces a single sporangium
Monocentric chytrids
several sporangia form on a network of rhizoids termed a rhizomycelium
Polycentric
monocentric, eucarpic, the largest
genus in the Chytridiales
Rhizophydium
Chytrids exist as obligately anaerobic symbionts in the intestines of herbivorous mammals now placed in phylum ________
Neocallimastigomycota
are saprotrophs as well as parasites of fungi, algae, plants and invertebrates, and may be facultatively anaerobic in oxygen-depleted environments.
BLASTOCLADIOMYCOTA
______ is anisogamous; female gametes are colorless and sluggish, male gametes are orange (they contain α-carotene) and very active, swimming in arcs interspersed with a jerky, tumbling, movement.
Allomyces
stimulates the influx of calcium ions (Ca2+) into the sperm cytoplasm and the physiological response is to reduce the length of the arc in the swimming of the male gametes
Sirenin
Besides sirenin, the sperm cells of Allomyces macrogynus produce a female attractant, called _________
parisin
comprises the subphyla Entomophthoromycotina, Kickxellomycotina and Zoopagomycotina;
Zoopagomycota
constitutes the earliest diverging lineage of zygomycetes and contains species that are primarily parasites and pathogens of small animals (e.g. amoeba, insects, etc.) and other fungi, that is, mycoparasites).
Zoopagomycota
comprises subphyla Glomeromycotina (Mortierellomycotina, and Mucoromycotina and is a sister phylum to the Dikarya (Ascomycota and Basidiomycota).
Mucoromycota
It is the more derived clade of zygomycetes and mainly consists of mycorrhizal fungi, root endophytes, and decomposers of plant material.
Mucoromycota
the earliest diverging clade of zygomycetous fungi.
Zoopagomycota
produced by some of the animal pathogens and mycoparasites.
Haustoria
Asexual reproduction is by ____________ from branched or unbranched conidiophores; primary conidia are forcibly discharged, and secondary conidia are either forcibly or passively released
conidiogenesis
Sexual reproduction involves the formation of either zygospores by _________ __________, involving hyphal compartments or hyphal bodies.
gametangial copulation
includes three classes and three orders of saprobic and insect pathogenic fungi.
ENTOMOPHTHOROMYCOTINA
species may be saprobes, mycoparasites, and symbionts of insects; the latter includes Harpellales that are typically found within the hindguts of aquatic life history stages.
KICKXELLOMYCOTINA
include mycoparasites and predators or parasites of small invertebrates and amoebae.
ZOOPAGOMYCOTINA
shares a most recent common ancestor with Dikarya and is characterized by plant symbionts, decomposers of plant debris, plant pathogens and only rare ecological interactions with animals (primarily opportunistic infections).
Mucoromycota
contains Archaeosporales, Diversisporales, Glomerales, and Paraglomerales
GLOMEROMYCOTINA
known as prolific producers of fatty acids, especially arachidonic acid and they frequently harbor bacterial endosymbionts.
Mortierella
This subphylum features the largest number of described species of Mucoromycota and includes the well-known model species Mucor mucedo and Phycomyces blakesleeanus. It also includes industrially important species of Rhizopus and other genera.
MUCOROMYCOTINA
a typical filamentous mould that occurs as a saprotroph in soil, and on decaying fruits and vegetables. It is found everywhere in nature.
Mucor
characterized by very fast growing and coarse hyphae and colonies spread by means of creeping aerial hyphae known as stolons that branch into pigmented root-like rhizoids when they contact the substratum
Rhizopus
another filamentous fungus in the order Mucorales.
Phycomyces blakesleeanus
produces numerous tall sporangiophores that are very sensitive to light.
Phycomyces
usually considered to be a member of the Entomophthorales. It is isolated from the dung of amphibians, reptiles, and insectivorous bats, as well as wood lice, plant debris and soil.
Basidiobolus
commonly found in soil and plant material, particularly in Mediterranean and subtropical zones.
Cunninghamella
the only known human and animal pathogen, another opportunistic fungus that may cause infections in immunocompromised hosts.
C. bertholletiae (Cunninghamella berthholletiae)
are also common soil fungi and the genus contains over 70 recognized species, however, M. wolfii is probably the only (again, opportunistic) pathogen of man and other animals in this genus.
Mortierella
The fungus grows inside the body of the insect. The mycelium of the fungus grows into the region of the fly’s brain that controls behaviour, inducing the fly to land on a nearby surface and crawl up as high as possible.
Entomophthora
the largest group in Kingdom Fungi. Filamentous fungi that produce a mycelium in which the hyphae are regularly septate
ASCOMYCOTA
Sexual spores (ascospores) are formed within a sac-like structure hyphal cell which is called an ______
Ascus
also known, informally, as the archiascomycetes
Taphrinomycotina
also known, informally, as the hemiascomycetes
Saccharomycotina
also known, informally, as the euascomycetes
Pezizomycotina
The four main ascoma morphologies are:
Apothecia, Perithecia, Cleistothecia, Ascostromata
typically disk- to cup-shaped to spoon-shaped (spathulate) and produce their asci in a well-defined tissue layer, a hymenium, which is exposed to the air.
Apothecia
partially closed stomata
Perithecia
completely closed stomata
Cleistothecia
the asci develop in preformed spaces, called locules and the stroma often forms a flask- shaped (pseudothecia) or open, cup-shaped (hysterothecia and thyriothecia) structure that resembles the gross morphology of perithecia or apothecia.
Ascostromata
The descriptive names for the major ascus types include:
prototunicate, operculate, inoperculate, bitunicate
produced by apothecial, cleistothecial and perithecial fungi; thin-walled, globose to broadly club-shaped, ascospores released passively by disintegration of the ascus wall.
prototunicate
found in apothecial fungi; release ascospores through a defined opening with a ‘lid’ (operculum) that is formed either at the ascus apex or just below it.
operculate
produced by apothecial, cleistothecial and perithecial fungi; typically thin-walled, the tip of the ascus usually has a small pore filled with loose wall material; the spores are discharged through this pore, or if there is no pore, dehiscence by rupture of the ascus apex.
inoperculate
conspicuously thick-walled with two walls, called the exotunica and endotunica; produced by ascostromatic lichenised and nonlichenised species and ascohymenial lichens
bitunicate
its members share the feature that their sexual spores are exospores, formed on a basidium (and are therefore called basidiospores).
BASIDIOMYCOTA
includes the plant pathogens that cause smut and rust diseases, ectomycorrhizal species which are of key significance to forest ecosystems, saprotrophic species that can decay the lignin (‘white-rot fungi’) as well the cellulose of plant litter, and the most noticeable and frequently encountered mushroom fungi.
BASIDIOMYCOTA
Species are based on morphological similarity, but most biologists and mycologists in particular, believe that the morphological species concept is the least satisfactory. It is practical for identification, but it obscures the phylogenetic origins of many features.
The morphological species concept
Species is defined as an interbreeding population that is somehow reproductively isolated from other populations. This cannot be applied to all fungi because within the group there are many that do not reproduce sexually. Overall, there are too many severe restrictions on application of the biological species concept widely in fungi for it to be a universal definition
The biological species concept
Differentiates species by their ecological niche and the constraints on their evolution that determine their maintenance and reproduction in that niche. The niche may be a particular species of host plant, or even a specific cultivar of a host species. Application is severely limited in practice. Can be ideal for pathogens butt there is a vast range of other fungi for which this approach simply fails. It is another concept that cannot offer the universal definition
Ecological and physiological species concepts
Envisages a species as being a monophyletic group of organisms sharing molecular characters that derive from a common ancestor. The concept does not have any obvious built-in exclusions or limitations. The analysis can be applied to asexual organisms; anamorphic and teleomorphic stages can be covered by a single species concept. No shortage of characters – fungal genomes are big enough to provide more than enough sequences for this to be a definition of universal applicability.
Evolutionary/phylogenetic species concept
This is an informal grouping that includes the most ancient fungi and fungus-like organisms
Water moulds
The organisms known as ______________ are now all placed in Kingdom Protozoa. They do not form hyphae, and they generally lack cell walls, being capable of ingesting food particles by phagocytosis.
Slime moulds
wood becomes markedly paler as the organism digests the (colored) phenolics in lignin. This mainly affects hardwoods and in a ____________, hemicellulose, cellulose and lignin are degraded more or less simultaneously.
White rot
wood becomes darker brown as the digestion proceeds. In this case hemicellulose and cellulose are preferentially removed, because the fungus does not degrade the lignin. This particularly affects softwoods.
Brown rot
a symbiotic interaction between fungi and plant roots that developed very early in the process of colonisation of the terrestrial environment.
Mycorrhiza
