General characteristic features

Most fungi are built from thin, branching, filamentous structures called hyphae, and a mass of interwoven hyphae together forms the mycelium. The fungal cell wall is made of chitin, a polysaccharide polymer of N-acetyl glucosamine (in contrast to the cellulose walls of plants). Based on whether cross-walls (septa) are present, mycelium is classed as either coenocytic (aseptate and multinucleate - the hypha is one continuous tube shared by many nuclei, as in the lower fungi, e.g. Albugo) or septate (divided by cross-walls into distinct cells, as in the higher fungi, e.g. Fusarium). Beyond individual hyphae, fungal tissue as a whole is organised into a loosely or compactly interwoven mass called plectenchyma, itself of two types: prosenchyma, where the hyphae run loosely but roughly parallel to one another, and pseudoparenchyma, where the hyphae are packed so tightly together that they lose their individual identity. Fungal thalli also differ in how completely they commit to reproduction: in holocarpic forms the entire thallus converts into the reproductive structure, while in eucarpic forms only part of the thallus reproduces and the rest stays veget …