The parts of a fungus that we do see are its fruit bodies, and
they consist of hyphae or modified hyphae. Most fungi start
their lives as tiny single- or many-celled fragments called
and the job of the fruit bodies is to produce and release these
spores to complete the organism's life cycle. Fruit bodies produce
spores sexually when cells on the same or separate hyphae mate.
The fungi of the divisions Ascomycota
also produce asexual spores known as conidia,
when special fragments separate from an individual hypha. The
fungi in the Zygomycota and the Oomycota have their spores borne
internally in a structure called a sporangium.
The spores are then called sporangiospores.
Fruit bodies come in a wide variety of shapes and sizes, from
the microscopic moulds to the giant puffball. The fungi that
we describe on this website mostly belong to one of two divisionsAscomycota
differ mainly in the structure of their fruit bodies. Most fungi
are filamentous and produce hyphae. Comparatively few are unicellular
and these are the yeasts. Unicellular yeast-like fungi have
evolved independently in both the Ascomycota
and in the Basidiomycota.