The fungi (singular fungus) are a kingdom of eukaryotic organisms. They are heterotrophic and digest their food externally, absorbing nutrient molecules into their cells. Yeasts, molds, and mushrooms are examples of fungi. The branch of biology involving the study of fungi is known as mycology.
Fungi often have important symbiotic relationships with other organisms. Mycorrhizal symbiosis between plants and fungi is particularly important; over 90% of all plant species engage in some kind of mycorrhizal relationship with fungi and are dependent upon this relationship for survival. Fungi are also used extensively by humans: yeasts are responsible for fermentation of beer and bread, and mushroom farming and gathering is a large industry in many countries.
Fungi and bacteria are the primary decomposers of organic matter in most terrestrial ecosystems.
Fungi were originally classified as plants, however they have since been separated as they are heterotrophs. This means they do not fix their own carbon through photosynthesis, but use carbon fixed by other organisms for metabolism. Fungi are now thought to be more closely related to animals than to plants, and are placed with animals in the monophyletic group of opisthokonts. For much of the Paleozoic Era, the fungi appear to have been aquatic. The first land fungi probably appeared in the Silurian, right after the first land plants appeared, even though their fossils are fragmentary. Fungi absorb their food while animals ingest it; also unlike animals, the cells of fungi have cell walls. For these reasons, these organisms are placed in their own kingdom, Fungi, or Eumycota.
The Fungi are a monophyletic group, meaning all varieties of fungi come from a common ancestor. The monophyly of the fungi has been confirmed through repeated tests of molecular phylogenetics; shared ancestral traits include chitinous cell walls and heterotrophy by absorption, along with other shared characteristics.
The taxonomy of the Fungi is in a state of rapid flux at present, especially due to recent papers based on DNA comparisons, which often overturn the assumptions of the older systems of classification.There is no unique generally accepted system at the higher taxonomic levels and there are constant name changes at every level, from species upwards.
2006-12-11 03:21:15
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answer #1
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answered by Anonymous
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The Kingdom Fungi contains such a huge variety of organisms that it's very hard to settle on a unifying set of characteristics. However, heterotrophy and the chitinous cell wall would appear to be characteristic of ALL fungi.
2006-12-11 04:41:33
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answer #2
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answered by Anonymous
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they don't have chlorophyl , they just hang around and feed off organic stuff and of course they all know how to have fun.
God bless,
gabe
2006-12-11 03:17:08
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answer #3
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answered by gabegm1 4
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