|MadSci Network: General Biology|
Molds are fungi. Fungi are coenocytic organisms composed of masses of tubes or filaments, called hyphae. Fungi are heterotrophic, they do not prfoduce their own food like plants (phototrophs). They must get their food from their environment. They get their food by secreting digestive enzymes to dissolve organic and inorganic food materials. They then absorb the soluble products from digestion.
There are tens of thousands of different kinds of fungi and they grow in a rainbow of colors. Some fungi are used to make dye, but that is a different subject! Other fungi are yeasts and mushrooms, but 'mold' generally refers to multicellular, filamentous fungi that do not produce large macroscopic fruiting bodies like mushrooms. Yeasts are most often single cell organisms, although there are filamentous yeasts. People who study fungi are 'mycologists'. There is almost nothing on earth that fungi won't eat. Which is fortunate for us because we would soon be buried in waste without fungi to decompose it. There are even fungi that can 'eat' toxic waste from the soil and turn it into harmless byproducts. Fungi can be picky about what they eat as well. There is a fungus that only grows on blond hair of boy babies. There is a fungus that only grows on the left hind leg of houseflies. There are fungi found only in the rear gut of millepedes.
Molds grow in every color imaginable. Look for Rhizopus stolinifera (black bread mold) on old bread. Look for Penicillium camenbertii on blue cheese--it is what makes blue cheese blue. The green fuzz on oranges that The green fuzz on oranges that have been around too long is also a Penicillium, from the same genera of organisms that gave us penicillin, that critical antibiotic. Fungi are a great boon to humankind. Without yeast, there would be no bread or beer. Fungi are used to make antibiotics, soy sauce, miso, sake, tufu,and many, many more foods. On the other hand, some of the most devestating plant diseases are caused by mold. The Irish Famine was caused by the potato blight, Phytophthera infestans. Most of the great American Chestnut forests where wiped out within 50 years by a fungus introduced into the U.S. in a tree planted in the New York Botanical Garden. Fungi are responsible for Trillions of dollars in damage every year from food spoilage around the world.
There are many fun facts about fungi to be found at Dr. Fungus on the Internet. Have fun!
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