أ.د.بان طه محمد

What is a fungus?

A fungus is a eukaryote that digests food externally and absorbs nutrients directly through its cell walls.

Most fungi reproduce by spores and have a body (thallus) composed of microscopic tubular cells called

hyphae. Fungi are heterotrophs and, like animals, obtain their carbon and energy from other organisms.

Some fungi obtain their nutrients from a living host (plant or animal) and are called biotrophs; others obtain

their nutrients from dead plants or animals and are called saprotrophs (saprophytes, saprobes). Some

fungi infect a living host, but kill host cells in order to obtain their nutrients; these are called necrotrophs.

Fungi were once considered to be primitive members of the plant kingdom, just slightly more advanced

than bacteria. We now know that fungi are not primitive at all. In fact, recent taxonomic treatments such as

the Tree of Life Project show that fungi and animals both belong to the group Opisthokonta (Fig. 1). Fungi

may not be our next of kin, but they are more closely related to animals than they are to plants. We also

recognize that organisms traditionally studied as "fungi" belong to three very different unrelated groups:

the true fungi in Kingdom Fungi (Eumycota), the Oomycetes, and the slime molds (Fig. 1).