When most people think of fungus, they picture a typical mushroom that you might find after a warm summer rain, under a big tree or by an old stump. Also, many people think of a mushroom cap and stalk, which are typically brown, making up the entire organism. Although these morphologies are stereotypical of fungi, they are certainly not the only fungi and are actually a very small part of the actual fungal structure (left and right). The majority of the organism is underground and found as hyphae. The mushroom found above ground is merely a means of spore dispersal, also called, a fruiting body.
Usually, when you see a patch of mushrooms, they're
all connected by hyphae, which make up the majority of the fungi. The
hyphae collect nutrients from the soil, transfer it to the rest of the
organism and, in mutualistic fungi, transfer it to the symbiont organism
as well. There are two types of hyphae found in all fungi. The first is
coenocytic hyphae (right), which doesn't have any septum (one continuous
cell). The other kind of hyphae does have septum (left), so there are
distinguishable cells. Both types of hyphae have their problems and they
also have their benefits. Septate hyphae are able to prevent the loss
of cytoplasm (if cut) by having septum that block off passage into adjoining
cells, where as coenocytic hyphae cannot. The coenocytic hyphae can, however,
transport molecules much easier and faster than septate hyphae.