The nuclei of all fungi, like that of other eukaryotic organisms, contains a nucleolus and several chromosomes that are bound by a nuclear membrane. Hyphal cells in septate hyphae may be uninucleate, binucleate, or multinucleate. For the most part, cellular and nuclear division are independent events, especially with respect to vegetative growth. As in other eukaryotic organisms, fungi have mitochondria, 80S ribosomes, and centrioles. The cell wall of fungi consist of chitin, chitosan, glucan, mannan, other components in various combinations.
Fungi are carbon heterotrophs, therefore they require preformed organic compounds as carbon sources.
Fungi do not contain chlorophyll. As an important contrast, the actinomycetes are prokaryotic gram positive filamentous bacteria. Historically, because of their microscopic morphology, some actinomycetes have been studied by medical mycologists. However, they are quite different. The actinomycetes serve as a host to bacteriophages, whereas fungi cannot serve as their host.