9 public questions tagged with this topic.
Alternaria, Colletotrichum and Trichoderma are examples of Deuteromycetes. Members of this group reproduce by asexual spores called conidia.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Fungi - Deuteromycetes and Economic Importance
In Ascomycetes and Basidiomycetes, plasmogamy may not be followed immediately by karyogamy. An intervening dikaryotic stage with two nuclei per cell, written as n + n, occurs and is called the dikaryophase.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Fungi - Phycomycetes Ascomycetes Basidiomycetes
Deuteromycetes are called imperfect fungi because only their asexual or vegetative phases are known. When their sexual forms are discovered, they are moved to the fungal classes to which they correctly belong.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Fungi - Phycomycetes Ascomycetes Basidiomycetes
Ascomycetes may be saprophytic, decomposers, parasitic or coprophilous. Coprophilous fungi grow on dung.
Ref: NCERT Class 11 Biology Chapter 2: Biological Classification Fungi - Phycomycetes Ascomycetes Basidiomycetes
Phylum Basidiomycota derives name from basidium, enlarged club-shaped meiosporangium where karyogamy followed by meiosis generates haploid spores. Typically four basidiospores develop exogenously on sterigmata tips, forcibly discharged via surface tension mechanism called Buller's drop. Dikaryotic mycelium persists with clamp connections maintaining paired nuclei, extensive hyphal fusion. Basidia aggregate in macroscopic basidiocarp exemplified by familiar mushrooms, puffballs, shelf brackets, stinkhorns, plus microscopic rusts and smuts. This morphology contrasts with sac fungi producing asci internally, zygomycetes forming zygosporangia and imperfect fungi lacking observed sexual reproduction entirely.
Ref: Campbell Biology 12th ed. Chapter 31 Fungi Basidiomycota; Alexopoulos Introductory Mycology 4th ed. Basidiomycetes
Rhizopus stolonifer commonly known as black bread mold belongs to Mucoromycota historically placed within Zygomycota sensu lato. Characteristics: coenocytic aseptate hyphae differentiated into stolons, rhizoids for anchorage and sporangiophores bearing black sporangia with columella containing sporangiospores, sexual zygospores at contact zone of opposite strains. Rapid growth on starchy substrates like bread highlights saprotrophic role decomposing carbohydrates. Ascomycota includes Penicillium producing conidia, Basidiomycota mushrooms, Chytridiomycota chytrids with flagella. Hence bread mold affiliation clearly aligns with zygosporic mucoralean fungi. Sporangiospores demonstrate rapid germination on carbohydrate-rich substrates like bread, fruits and dung illustrating saprotrophic efficiency and spoilage capacity.
Ref: Campbell Biology 12th ed., Chapter 31: Rhizopus Zygomycota Bread Mold; NCERT Class 11 Phycomycetes Bread Mold; NCBI Mucorales Taxonomy
Vegetative hyphae septation pattern serves important taxonomic criterion distinguishing fungal phyla. Zygomycetous fungi within Mucoromycota possess coenocytic aseptate hyphae lacking regular cross-walls, nuclei moving freely through continuous cytoplasm except when delimiting reproductive organs. Ascomycota and Basidiomycota exhibit septate hyphae with perforate septa containing pores. Deuteromycota artificial group also septate. Absence of septa facilitates rapid cytoplasmic streaming and growth but increases vulnerability to injury. Therefore group lacking septa in vegetative stage among given choices is Zygomycota, reflecting early divergence before evolution of regular septation.
Ref: Campbell Biology 12th ed., Chapter 31: Zygomycota Aseptate Coenocytic; NCERT Class 11 Phycomycetes Coenocytic Mycelium; NCBI Mucoromycota
Basidiomycota maintain extended dikaryotic phase dominating life cycle, often persisting years in wood-decaying mycelium or forming expansive fairy rings spanning meters. After plasmogamy clamp connections ensure each compartment inherits n+n nuclei; true diploid only transient in basidium before meiosis. Ascomycota have brief dikaryon confined to ascogenous hyphae, Zygomycota lack dikaryon entirely undergoing immediate karyogamy, Chytridiomycota lack. Prolonged dikaryotic growth enables massive basidiocarp development, genetic complementation and outcrossing advantage, characteristic feature exploited for mushroom cultivation and forest mycorrhizal symbiotic networks. This feature underpins diagnostic microscopy, molecular phylogenetics and evolutionary understanding crucial for NEET, CBSE and competitive examinations requiring precise conceptual clarity.
Ref: Campbell Biology 12th ed., Chapter 31: Basidiomycota Prolonged Dikaryotic Phase; NCERT Class 11 Dikaryon; NCBI Dikaryotic Mycelium
Ascomycota called sac fungi produce sexual meiospores termed ascospores internally within sac-shaped meiosporangium called ascus where karyogamy and meiosis occur. Typically yields eight ascospores after additional mitotic division ensuring efficient dispersal. Asci grouped into ascocarps such as cleistothecia, perithecia. Zygomycota produce zygospores, Basidiomycota basidiospores externally on basidia, Chytridiomycota zoospores motile. Presence of asci with endogenous ascospores represents synapomorphy diagnostic for Ascomycota comprising yeasts, molds, morels, truffles encompassing largest fungal phylum with significant medically and industrially important members. Basidial morphology supports diverse basidiocarp architectures from simple crusts to elaborate mushrooms facilitating ecological niche specialization and spore liberation.
Ref: Campbell Biology 12th ed., Chapter 31: Ascomycota Ascus Ascospores; NCERT Class 11 Biology Ascomycetes; NCBI: Ascomycete Reproduction
