Mushroom K-12 Experiments
Mushroom Background
Basidiocarps (mushrooms) of the fungus Leucocoprinus sp.
A mushroom (Old English muscheron, from the Old French mouscheron, French mousseron (same name in English, for a common kind of mushroom), itself perhaps from mousse, meaning moss) is an above-ground fruiting body (that is, a spore-producing structure) of a fungus,
having a shaft and a cap; and by extension, the entire fungus producing
the fruiting body of such appearance, the former consisting of a
network (called the mycelium) of filaments or hyphae. In a much broader sense, mushroom
is applied to any visible fungus, or especially the fruiting body of
any fungus, with the mycelium usually being hidden under bark, ground,
rotted wood, leaves, etc. Mushrooms obtain food through decomposition.
The technical term for the spore-producing structure of "true"
mushrooms is the basidiocarp. The term "toadstool" is used typically to designate a basidiocarp that is poisonous to eat.
Types of mushrooms
Mushrooms are often dried in order to preserve them for use in cooking.
The main types of mushrooms are agarics (including the button mushroom, the most common mushroom eaten in the U.S.), boletes, chanterelles, tooth fungi, polypores, puffballs, jelly fungi, coral fungi, bracket fungi, stinkhorns, and cup fungi. Mushrooms and other fungi are studied by mycologists. The "true" mushrooms are classified as Basidiomycota (also known as "club fungi"). A few mushrooms are classified by mycologists as Ascomycota (the "cup fungi"), the morel and truffle being good examples. Thus, the term mushroom is more one of common application to macroscopic fungal fruiting bodies than one having precise taxonomic meaning.
Edible mushrooms are used extensively in cooking,in many cuisines.
Though commonly thought to contain little nutritional value, many
varieties of mushrooms are high in fiber and protein, and provide
vitamins such as thiamine, riboflavin, niacin, biotin, B12 and ascorbic acid, and minerals including iron, selenium, potassium and phosphorus. However, a number of species of mushrooms are poisonous,
and these may resemble edible varieties, although eating them could be
fatal. Picking mushrooms in the wild is risky — riskier than gathering
edible plants
— and a practice not to be undertaken by amateurs. The problem is due
to the fact that separating edible from poisonous species is dependent
upon the application of only a few easily recognizable traits. People
who collect mushrooms for consumption are known as mushroom hunters,
and the act of collecting them as such is called mushroom hunting.
Mushroom structure
These emerging mushrooms are too immature to safely identify the species
the relative sizes of the cap and the pileus vary widely.
Identifying mushrooms requires a basic understanding of their macroscopic structure. A "typical" mushroom consists of a cap or pileus supported on a stem or stipe. Both can have a variety of shapes and be ornamented in various ways. The underside of the cap (in agarics) is fitted with gills or lamellae
where the actual spores are produced. How the gills are attached is
another important characteristic used in identification. In the boletes, the gills are replaced by small openings called pores. Bracket fungi
essentially lack a stipe, and the cap is attached like a bracket to the
substratum, usually a log or tree trunk. Some bracket fungi have gills,
others have pores.
In general, identification to genus can be accomplished in the field using a local mushroom guide. Identification to species,
however, requires more effort; one must remember that a mushroom
develops from a young bud into a mature structure and only the latter
can provide certain identification of the species. Examination of
mature spores, or at least knowing their color, is often essential. To
this end, a common method used to assist in identification is the spore print.
Apical Germ Pore
Apical Germ Pore is a term applied to mushroom spores which have a pore at one end. Some spores have a hole in the cell wall where the first strand of germinating mycelium emerges. If the cell wall is divided from one end to the other, this is called a germ slit. Commonly the germ pore is at one end of the mushroom spore and is called an apical pore.
Mushroom genera with apical germ pores include Agrocybe, Panaeolus, Psilocybe, and Pholiota.
Chemical properties
Of central interest with respect to chemical properties of mushrooms
is the fact that many species produce secondary metabolites that render
them toxic, mind-altering, or even bioluminescent.
Toxicity likely plays a role in protecting the function of the
basidiocarp: the mycelium has expended considerable energy and
protoplasmic material to develop a structure to efficiently distribute
its spores. One defense against consumption and premature destruction
is the evolution of chemicals that render the mushroom inedible, either
causing the consumer to regurgitate (see emetics) the meal or avoid consumption altogether (see Mushroom poisoning).
Psilocybin mushrooms possess psychedelic properties. They are commonly known as "magic mushrooms" or "shrooms", and are available in smart shops in many parts of the world (see Psychedelic mushroom). A number of other mushrooms are eaten for their psychoactive effects, such as fly agaric, which is used for shamanic purposes by tribes in northeast Siberia. A popular myth claims that the Vikings used fly agaric to induce a berserker mind state, but this has no historical backing.
Currently, many species of mushrooms and fungi utilized as folk medicines for thousands of years are under intense study by ethnobotanists and medical researchers. Maitake, shiitake, and reishi are prominent among those being researched for their potential anti-cancer, anti-viral, and/or immunity-enhancement properties.
Psilocybin,
originally an extract of certain psychedelic mushrooms, is being
studied for its ability to help people suffering from mental disease,
such as Obsessive-compulsive disorder. Minute amounts have been reported to stop cluster and migraine headaches. It has also been used in the west to potentiate religious experience. See Good Friday experiment
Because of their psychoactive properties, some mushrooms have played
a role in native medicine, where they have been used to effect mental
and physical healing, and to facilitate visionary states. One such
ritual is the Velada ceremony. A representative figure of traditional mushroom use is the shaman, curandera (priest-healer), Maria Sabina.
Some mushrooms have been used as fire starters (known as tinder fungi). Ötzi the Iceman was found carrying such mushrooms.
See also
External links
Further reading
This article is licensed under the GNU Free Documentation License. It uses material from Wikipedia Encyclopedia article "Mushroom"
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