sexual
hyphae divided by perforated septa, allowing streaming of cytoplasm from one cell to the other. Conidia and asci, which are used respectively for asexual and sexual reproductions, are usually separated from the vegetative hyphae by blocked non-perforated septa. Asexual reproduction is frequent and involves the production of conidiophores that release haploid conidiospores Figure 24.13 . Sexual reproduction starts with the development of special hyphae from either one of two types of mating strains Figure 24.13 . The male strain produces an antheridium and the female strain develops an ascogonium. At fertilization, the antheridium and the ascogonium combine in plasmogamy without nuclear fusion. Special ascogenous hyphae arise, in which pairs of nuclei migrate: one from the male strain and one from the female strain. In each ascus, two or more haploid ascospores fuse their nuclei in karyogamy. During sexual reproduction, thousands of asci fill a fruiting body called the ascocarp. The diploid nucleus gives rise to haploid nuclei by meiosis. The ascospores are then released, germinate, and form hyphae that are disseminated in the environment and start new mycelia Figure 24.14 .