Physiological and Morphological Traits
There are a number of characteristics that distinguish fungi from other eukaryotic organisms.
- Fungi cannot make their own food like plants can since they do not have any of the
right equipment for photosynthesis. Fungi are more like animals and some bacteria in
that they have to obtain their food from outside sources. - The cell walls in lots of species of fungi is chitin. Chitin is a nitrogen-containing
material that you find in the shells of animals such as beetles and lobsters. But the
cell wall of a plant is not made of chitin but rather a carbohydrate called cellulose. - Unlike many plants, most fungi do not have a good vascular system. A vascular system
is the way that an organism transports fluids such as water and nutrients. In all plant
the vascular system is made up of structures called xylem and phloem. But fungi do
not have xylem or phloem. This lack of vascular structures distinguishes fungi from
plants. - However, one characteristic is entirely unique to fungi and does not exist at all in ani-
malsorplants. Thatcharacteristicishyphaewhichcombineingroupscalledmycelium,
as described above.
The Evolution of Fungi
Fungi appeared during the Paleozoic Era, a geologic time period lasting from about 570
million to 248 million years ago, and the time when fish, insects, amphibians, reptiles, and
land plants appeared. The first fungi were most likely aquatic, and had flagellum that
released spores. The first land fungi probably appeared in the Silurian period (443 million
years ago to about 416 million years ago), a geologic period during which land plants also
appeared.
Roles of Fungi
Fungi are found all over the globe in many different kinds of habitats. Fungi even thrive in
deserts. Most fungi however are found on land rather than in the ocean, but some species
live only in marine habitats. Fungi are extremely important to these ecosystems because
they are one of the major decomposers of organic material in most terrestrial ecosystems.
Scientists have estimated that there are nearly 1.5 million species of fungi.
Importance of Fungi for Human Use
Humans use fungi for food preparation or preservation and other purposes. For example,
yeasts are required for fermentation of beer, wine and bread (Figure9.11). Some fungi are
used in the production of soy sauce and tempeh, a stable source of protein, like tofu, found