Pregunta:
Talk about ascomycota reproduction
Autor: H KRespuesta:
In Ascomycetes, sexual reproduction begins when the hyphae of two different strains of sac fungi become closely associated. Antheridia are formed on the mycelium of (-) strain and oogonia on the other one (+). The male nuclei of the antheridium pass into the ascogonium via the trichogyne which is an outgrowth of the ascogonium (2) and pair with the female nuclei present but do not unite - Plasmogamy takes place. New dikaryotic hyphae (= dikaryon) develop from this fused structure (3). The cells at the tip of these hyphae form asci (sing. ascus), sac like structure (4), in which karyogamy (nuclear fusion) occurs. These asci (along with the sterile filaments paraphyses) are embedded in an ascocarp, the fruiting body of the fungus. Karyogamy in the asci is followed immediately by meiosis (5) and the production of ascospores (endogenous) (6, 7). The ascospores are disseminated (8) and germinate (9) to form new haploid mycelium. Asexual conidia may be produced by the haploid mycelium (10). In this life cycle, plasmogamy and karyogamy are separated in time and space by a dikaryotic phase.
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