Fungi Lecture Notes: Ascomycota, Basidiomycota, Lichens, and Mycorrhizae (Vocabulary)

Vocabulary flashcards covering key terms and concepts from the Fungi lecture notes (Ascomycota, Basidiomycota, lichens, and mycorrhizae).

Ascomycota

Phylum of fungi known as sac fungi; about 32,300 species; includes yeasts, mildews, ergot, morels; asci produce ascospores in sacs.

Taphrinomycotina

Subphylum of Ascomycota consisting mainly of single-celled yeasts (Neolecta is an exception).

Saccharomycotina

Subphylum of Ascomycota consisting of single-celled yeasts.

Pezizomycotina

Largest subphylum of Ascomycota; hyphae-producing; about 40% form lichens.

Hypha

Thread-like filament that makes up most of a fungus; hyphae are partitioned into cylindrical cells.

Septa with pores

Cross walls in hyphae with pores that allow passage of nuclei and cytoplasm between cells.

Monokaryotic hypha

Hypha with a single haploid nucleus per cell; early stage before mating-type fusion.

Homothallic

Fungi capable of self-fertilization; possess both mating types within one organism.

Heterothallic

Fungi requiring two compatible mating types for sexual reproduction.

Conidia

Asexual spores produced externally outside a sporangium, often at hyphal tips on conidiophores; usually multinucleate.

Conidiophore

Hyphal stalk that bears conidia at its tips.

Ascus

Sac-like cell in which haploid asci develop; contains ascospores.

Ascocarp (ascoma)

Fruiting body of Ascomycota in which asci form.

Ascospore

Haploid spore produced inside an ascus by meiosis.

Antheridium

Male gametangium that produces male nuclei for mating.

Ascogonium

Female gametangium that receives male nuclei during mating.

Trichogyne

Cytoplasmic bridge through which nuclei move from antheridium to ascogonium.

Plasmogamy

Fusion of cytoplasm from two haploid partners; nuclei may remain separate (dikaryon) before karyogamy.

Karyogamy

Fusion of nuclei to form a diploid zygote nucleus.

Crozier

Hook-shaped cell at the tip of ascogenous hypha where nuclei divide and form two cells (one male, one female).

Ascogenous hypha

Dikaryotic hypha that grows to form asci and contains one male and one female nucleus.

Dikaryotic (n+n)

Hyphal cells containing one nucleus from each mating type until karyogamy occurs.

Hymenium

Layer in which asci are produced on the surface of an ascocarp.

Apothecium

Cup-shaped ascocarp with exposed hymenium.

Cleistothecium

Completely closed ascocarp with no opening.

Perithecium

Flask-shaped ascocarp with a small opening (ostiole).

Paraphyses

Sterile hyphae interspersed among asci in the hymenium.

Thallus

Vegetative body of a lichen or fungus.

Yeast

Single-celled fungi; reproduce asexually by budding; can participate in sexual cycles via ascogonia/antheridia or form a diploid fusion cell.

Budding

Asexual yeast reproduction where a daughter cell forms as a bud and nuclei divide.

Saccharomyces cerevisiae

Common yeast used in bread, beer, sake, cider, and wine; first eukaryote genome sequenced.

Morchella (Morels)

Genus of edible mushrooms prized as delicacies.

Tuber melanosporum

Black truffle; highly prized edible fungus.

Ergot

Fungal disease of grains (ergot) that can cause ergotism (hysteria, convulsions, sometimes death).

Cryphonectria parasitica

Fungal pathogen causing chestnut blight and major American chestnut die-off.

Fusarium oxysporum

Fungal pathogen that caused Gros Michel banana wilt; led to switch to Cavendish variety.

Gros Michel

Banana cultivar largely wiped out by Fusarium wilt in the mid-20th century.

Cavendish

Current dominant banana cultivar; resistant to the strains that devastated Gros Michel.

Basidiomycota

Fungal phylum with about 22,300 species; includes puffballs, smuts, shelf/bracket fungi, jelly fungi, earth stars, toadstools, stinkhorns.

Basidium

Basidia are the spore-bearing cells on which basidiospores form (outside the hyphae in many basidiomycetes).

Basidiospore

Haploid spore produced on a basidium; disperses to form new mycelium.

Basidiocarp (basidioma)

Fruiting body of Basidiomycota where basidia produce basidiospores.

Clamp connections

Nuclear-pairing structures in dikaryotic basidiomycete hyphae that ensure each new cell receives one nucleus of each mating type.

Pileus

Cap of a mushroom.

Stipe

Stalk or stem of a mushroom.

Gills

Lamellate plates on the underside of the pileus where basidia and basidiospores form.

Annulus

Ring around the stipe left from the lifting of the universal veil.

Volva

Cup-shaped structure at the base of the stipe in some species; remnants of the universal veil.

Sterigmata

Small projections from basidia through which basidiospores are born and released.

Basidia

Swollen ends of basidia on which meiosis occurs to form four basidiospores.

Puffball

Gasteromycete that releases spores when the enclosing peridium breaks.

Earthstar

Gasteromycete with outer husk that peels back to reveal an internal spore mass.

Stinkhorn

Gasteromycete with a smelly gleba that attracts insects for spore dispersal.

Birds-nest fungus

Cup-shaped fruiting body with spore-containing 'eggs' that are ejected by rain splash.

Pucciniomycotina

Basidiomycete subphylum consisting mainly of rusts; ~8000 species; parasitize plants; life cycles often complex.

Puccinia graminis

Cause of black stem rust of wheat; heteroecious and life cycle involves two hosts.

Heteroecious

Requires two unrelated host species to complete the life cycle.

Sori

Clusters or masses of spore-producing structures on plants (rusts) or fungi.

Gymnosporangium juniperi-virginianae

Apple-Cedar Rust; rust fungus with a two-host life cycle.

Ustilaginomycotina

Basidiomycete subphylum; smuts; mycelium grows between host cells; typically autoecious or heteroecious.

Ustilago maydis

Cause of common corn smut; develops dark spores inside enlarged kernels.

Smuts

Parasitic Basidiomycota on flowering plants; usually dark spores; often autoecious.

Autoecious

Life cycle can complete on a single host.

Deuteromycota

Fungi Imperfecti; fungi with no observed sexual stage; reproduce asexually by conidia; sometimes later found to have sexual stages.

Fungi Imperfecti

Former name for Deuteromycota; fungi lacking known sexual reproduction.

Penicillium

Genus that produced penicillin; source of the first antibiotic.

Aspergillus oryzae

Aspergillus species used in fermenting soybeans to make soy sauce.

Aspergillus sojae

Aspergillus species used in producing soy sauce and other fermented foods.

Lichens

Symbiotic association of a fungus and an alga or cyanobacterium; treated as a single organism; 13,500–17,000 species.

Photobiont

Photosynthetic partner in a lichen (alga or cyanobacterium).

Mycobiont

Fungal partner in a lichen.

Crustose

Lichen growth form that is crust-like and tightly attached to the substrate.

Foliose

Leaf-like lichen growth form; typically loosely attached.

Fruticose

Shrub-like, highly branched lichen form.

Fairy Ring

Circular ring of mushrooms formed by outward-growing mycelium.

Mycorrhizae

Mutualistic associations between fungi and plant roots; fungi aid water and nutrient uptake; plants provide carbohydrates.

Endomycorrhizae

Also called arbuscular mycorrhizae; fungal hyphae penetrate root cells; widespread and not highly host-specific.

Ectomycorrhizae

Fungi form a sheath around outside of roots; common in oaks, willows, pines; specialized plant relationships.