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Fungi
Fungi are plant-like organisms that are parasites of either dead or living organic matter. These parasitic fungi (as opposed to the saprophytic fungi) absorb small nutrient molecules from the cells of living hosts. Many fungi are also pathogenic (disease-producing) in other living animals, as well as plants. Since they are parasites that live on others, fungi contain no chlorophyll and cannot carry out photosynthesis.
Fungi share a basic body plan common in most multicellular species. More than 100,000 different species of fungi have been identified, and they are grouped into just four different phylia.
<== Spongecake Clathrus (Clathrus columnatus)
Photographer: Randolph Femmer, National Biological Information Infrastructure
1. PHYLUM BASIDIOMYCETES (The Club Fungi)
They got their name because of the tiny, "club"-shaped basidia ("little bases") growing out from the gills under the mushroom caps. The basidia are important because they produce the mushroom's spores or seeds for reproduction. This phylum includes forms commonly known as mushrooms, boletes, puffballs, earthstars, stinkhorns, bird's-nest fungi, jelly fungi, bracket or shelf fungi, and rust and smut fungi.
2. PHYLUM ASCOMYCETES (The Sac Fungi) or "leather bag" (asco-) fungi. This group is commonly called the sac fungi because they produce spores within their sac-like or bag-like caps. This group also includes yeast. Yeast cells reproduce by smaller cells budding off and eventually separating from larger ones. Yeast belonging to the genus Saccharomyces are the main sugar ("sacchar") "fungi" (myc). This genus of yeast has been used to help make bread, beer and wine since ancient times. Some common ypes of molds also belong to this group. A familiar example of such molds is the genus Penicillium, bluish-colored molds growing on bread, fruits, and cheeses.
<== Scarlet Caterpillar Club (Cordyceps militaris)
Photo credit: ocid.nacse.org
Several Penicillium species produce penicillin, the powerful, bacteria-killing, antibiotic drug. Another example is aspergillus causing nfections of the nervous system and lungs. Most pathogenic fungi with a known perfect state belong to this phylum.
3. PHYLUM ZYGOMYCETES "Zygo" literally means "yoked together." This phylum of fungi derives its name from the inclusion of a zygote within its life cycle. A zygote consists of two sex cells, called gametes that are literally fused, yoked, or "maried" (gamet) together during fertilization. a typical zygomycetic fungus is the black bread mold, genus Rhysopus. a spore lands on a piece of white bread, then begins to germinate. The landed spore "sprouts" a number of thred-like filaments (hyphae), which soon merge to form a white, extensively branched mycelium, deep inside the bread slice. Soon, a large number of round-topped sporangia or "seed" (spor) "vessels" (angi), appear like tiny black puffballs. The mold is called Rhyzopoda, because the sporangia and their stalks are firmly anchored into the bread surface by means of rhizoids - blunt, root-resembling or foot-resembling projections. species in this phylum are usually saprophitic or usually saprophytic (obtaining its nutrients form dead or decaying organic materials) or parasitic, especially for insects.
4. PHYLUM CHYTRIDIOMYCETES or "water-dwelling" (chytrid) "fungi." These are the most primitive fungi dwelling in a water environment. Each chytrid has a small, globe-shaped bdy. It produces a highly active spore which has a flagellum ( a fine, hair-like process of a cell, associated with locomotion in a unicellular organism) attached. IN their adult stage, the chytrids make a large mycelium (network) consisting of an extensive tangle of slender hyphae. These highly branched hyphae create a large area for the easy absorption of nutrients dissolved in the suroounding water. They are the only fungi that produce motile cells at some stage in their life cycle. Most are saprobes (feeding on dead or dying animals or plants) but they also contain examples of plant, animal and fungal pathogens.
Source: REF FILE # PL-101
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