Fungi specialize in decomposition. They eat and decompose dead plants, dead animals, paint, shoes, plastic, film, paper, cloth and even gasoline and jet fuel. Fungi have been know to clog up gas lines in cars, and fuel lines in jet planes. In a moist climate like that of Louisiana, fungi can even live in human lungs.
Fungi which feed on dead plants and animals are called saprobes. Other fungi are parasites. Fungi secrete enzymes which digest outside of the fungi, then the fungi absorb the digested nutrients. The fungi body includes a mycelium composed of a mesh-work of microscopic filaments that spread all over the food source. Each filament is called a hyphae. Hyphae are reinforced with chitin which protects the hyphae. Chitin is a carbohydrate.
Fungi can be very large. Several years ago a fungi was discovered in Michigan which was an acre in size. Fungi reproduce sexually and asexually. Asexually, they reproduce by forming spores, fragments of hyphae, or binary fission. Sexually, they divide by binary fission, but each new cell is haploid. Haploid means that they have only half of their normal number of chromosomes. The haploid cells grow, and then unite with other haploid cells to form a complete fungus. This type of sexual reproduction is called dikaryotic reproduction.
The fungi called Oomycota reproduce by spores which have flagella. Most Oomycota are plant parasites. The Oomycota Phytophthora infestans infects tomatoes and potatoes. Phytophthora infestans produced the potato blight which caused the Great Potato Famine in Ireland between 1845-1860. This led to wide spread Irish immigration to America.
A fungus in the class called Zygomycota causes black bread mold. The Zygomycota known as Ascomycota are used to make bread and alcoholic beverages. Another Zygomycota forms truffles, a favorite pig food.
Another class of fungi are the Basidiomycota or the club fungi. Basidiomycota are mushrooms. Agaricus brunescenes is an edible mushroom. However, others are poisonous and still others are hallucinogenic.
Another class of fungi is Deuteromycota. A Deuteromycota, known as aspergillus produces the lemon flavor which is used to make lemon drops. It is preferred to real lemon because real lemon is an oil that is not soluble in water. Another Deuteromycota is Penicillin, the antibiotic. Species of Deuteromycota produce athletes foot (ring worm), dandruff and jockey itch.
Lichens are a combination of a fungus and cyanobacteria, or a fungus and algae.
They are found on rocks and the outer surface of trees. Some lichens can
decompose rock. Lichens are not a species, but a symbiotic association. A
symbiotic association is when two species live together for the benefit of both.