Mushroom Biology: The Structure and Function of Mushrooms
Let's clear up a common misconception — mushrooms are NOT plants.
Mushrooms are a type of fungus. There are many different kinds of fungi, including molds and crusts.
Fungi are distinct from plants because they do not possess chlorophyll, the green pigment
that allows plants to manufacture sugar from the sun's energy. They need to absorb their food from the
environment in which they live.
Only about 3% of known mushroom varieties are poisonous, and the symptoms of poisoning can vary
from gastrointestinal discomfort to death, depending on the type of toxin ingested.
Fungi use fibers called hyphae, referred to as mycelium, to take in food.
The mycelium can remain dormant under the ground for many seasons, similar to the roots of plants.
Each hypha that is sent out makes its way through earth, wood and plant matter until it reaches the
surface.
During the organism's specific growing season, the hyphae develop into mature structures capable of
reproducing spores. The structure that you normally see above the ground is the part of the mushroom
that is producing and dispersing spores.
Each spore is a single cell that is capable of sending out a hypha that will develop into a group and form
its own mycelium. If the hypha of one spore meets up with the hypha of another, it begins the sexual process
of spore production through special spore-producing cells.
There are two types of spore-producing cells: asci and basidia. In asci,
the spores are fully contained within an outer covering. When the spores mature, the tip of the ascus breaks
open and the spores are released. In basidia, the spores are produced externally. The spores are released
when they break off.
Mushroom Gills
The spore of a mushroom contains all of the necessary materials to form a new fungus. When the spores of
a mushroom are released, they may travel a certain distance before they land. The single cell then sends out
hyphae to help establish the fungus and gather food.
After the spore has sent out its hyphae, they will eventually meet up with the hyphae of another mushroom.
After the sexual process of reproduction has begun, the mushroom forms the structures of a "fruiting body"
that will eventually produce and disperse spores. The egg/button stage is the early form of this fruiting body.
The mature fruiting body can have various structures. The fruiting body may contain a cap, stalk, ring,
volva, and gills. The cap normally houses the spore producing surface of the fruiting body.
Cup Fungi: The spore-producing asci are located on the inner surface of the mature fruiting body.
Spores are released in a cloud when the asci break open.
Gilled Mushrooms: Gilled mushrooms have basidia located on the gills on the underside of the cap.
The spores are dropped from the gills when mature.
Boletes Mushrooms The basidia are located in tubes within the flesh of the cap of the mushroom.
The spores are released through pores in the surface of the underside of the cap.
Puffball Mushrooms: The basidia in puffballs are contained entirely within the body of the mushroom.
A cloud of spores is released when the outer covering collapses or explodes.
Mushroom Spore Print.
One of the most popular
and easy ways to assist in
the identification of a fungi
is with what’s called a spore
print.
Only about 3% of known mushroom varieties are poisonous, and the symptoms of poisoning can vary
from gastrointestinal discomfort to liver failure and death, depending on the type of toxin ingested.
Acute liver failure from mushroom poisoning is relatively less common, but it does happen. And in the
majority of cases, it’s because an amateur mushroom hunter or backyard forager misidentified a
mushroom.
The most common dangerous mushrooms are those belonging to the Amanita genus, especially
Amanita phalloides, aptly called “death cap” mushrooms. They contain toxic compounds called
amatoxins that damage liver cells.
In less poisonous varieties, digestive symptoms of mushroom poisoning develop as early as 20
minutes to four hours after ingestion and normally pass after the irritant is expelled.
Morel Mushroom
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Oyster Mushroom
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Chanterelle Mushroom
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Soil Biology and The Food Web
Soil Health and Micro-organisms
The Wood Wide Web-How Fungi Shapes Our Forests
How To Help Beneficial Fungi
Fungi Quiz: Test Your Knowldege