The shape of a fungus depends on its type. The kingdom of fungi includes multi-cellular molds, unicellular yeasts (which are oval or spherical), and macroscopic species like mushrooms.

The thallus (body) of molds or fleshy fungi, such as mushrooms, consists of hyphae (long filaments of cells joined together):

· septate hyphae (in most molds) contain septa (cross-walls) that divide the hyphae into distinct, uninucleate (one nucleus) cell-like units.

· coenocytic hyphae (in a few classes of fungi) contain no septa and look like long continuous cells with many nuclei.