depends on mitosis and the rapid manufacture of cytoplasm; fungal mitosis is unique in that it occurs within the nucleus. Hyphae from genetically distinct individuals may fuse to form a heterokaryon-a single cytoplasm with dissimilar nuclei.
菌丝生长形成分支，进而形成网状结构称为菌丝体。在菌丝尖端，食物被消化并吸收；这个过程能持续产生更多菌丝。结果，真菌生长很快。生长靠有丝分裂和细胞质的快速产生。真菌的有丝分裂很独特，即它只发生在细胞核里。遗传学明显不同的菌丝个体融合形成异核体——同一个细胞质中含有不同的细胞核。
