The Kingdom of Fungi:
As noted, the fungal world includes smuts,
rust, mildew, yeast, mushrooms, and mold. Specialists
would insist that all these forms of fungi have their roles
to play in the complex ecosystems we have on this Planet,
some are even useful, such as yeasts used in the food industry,
culinary and medicinal mushrooms, and anti-bacterial molds
used to make both natural and pharmaceutical medicine.
Yeasts:
Unicellular fungi that reproduce by budding
or fission. A typical example affecting health would
be Candida albicans. As with molds, there are yeasts
that are used commercially as well as those that are pathogenic.
Just as scientists were unsure how to classify
fungi, the borderline between yeasts and molds is not hard
and fast. In theory, the difference between yeasts and
molds is mainly in their methods of reproduction. Yeasts
are asexual and "fruit" or "bud" daughters;
however, there are yeasts, including Candida albicans, that
sprout a hypha which penetrate mucosal membrances and become
much more irritating and destructive.