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A Feast at Plimoth

Feast or Famine

Truth or Consequences

Superfoods

Mushroom Mania

The Bite Stuff
in the classroom
TEACHING GUIDES


ABOUT ALL YOU CAN EAT: Mushroom Mania


Chefs the world over prize the elusive morel mushroom -- second only to the very rare and expensive truffle. For almost a century, scientists have tried to grow the morel in the lab and failed, puzzled by the little-understood life cycle of the fungus. But researchers in Michigan believe they have solved the mystery. Now, mushroom growers will be able to cultivate the tasty delicacy. Frontiers joins a hunt for the wild morel and records the first taste test of the cultivated morels.

Curriculum Links
Activity 1: How Much Do You Know About Mushrooms?
Activity 2: Taxonomic Facts of Life
Activity 3: Make a Spore Print
More About Mushrooms



CURRICULUM LINKS

BIOLOGY

fungi kingdom, mycology,
taxonomy
BOTANY

plant reproduction
CAREER EDUCATION

chef, restauranteur
EARTH SCIENCE

fungi, ecosystems


GENERAL SCIENCE

photosynthesis,
three kingdoms
HOME ARTS

cooking,
food preparation
LIFE SCIENCE


nonphotosynthetic
processes
SOCIAL STUDIES

agriculture, Mesoamerica



ACTIVITY 1: HOW MUCH DO YOU KNOW ABOUT MUSHROOMS?

Mushrooms. They grow in the dark, they feed off decaying organisms, they are sometimes poisonous and of more than 30,000 species, only a few varieties are eaten. Despite all their mystery, mushrooms are a source of botanical fascination and culinary delight; some species cost over $200 a pound. The activities here will expand your knowledge of the humble fungus.

FUNGUS FACTS

Are the following statement true or false?

  1. People began eating mushrooms only a century ago.

  2. Mushrooms have no nutritional value.

  3. Mushrooms are low in calories.

  4. Poisonous species of mushrooms look different from edible ones.

  5. Mushrooms do not undergo photosynthesis.


ANSWERS
  1. F. Although mushrooms have been cultivated commercially in the U.S. for about a century, they've been considered a delicacy since ancient times. In fact, Romans fed this "food of the gods" to soldiers before battle.

  2. F. They contain essential amino acids, potassium, some B vitamins and some minerals.

  3. T

  4. F. They may look almost identical.

  5. T




ACTIVITY 2: TAXONOMIC FACTS OF LIFE

Until recently, biologists recognized only two kingdoms of life on earth -- plants and animals. Fungi were considered part of the plant kingdom. Today's classification system recognizes at least three additional kingdoms: Monera (bacteria), Protista (algae, protozoa) and Fungi, a large group of simple plants that contain no green color, including molds, yeasts and mushrooms.

Taxonomic names for all living organisms are written in scientific language, either in Latin or Greek. Each two-part name gives the genus (group) and the species (individual). Humans belong to the genus Homo ("man") and the species sapiens ("wise"). Thus the taxonomic name for humans is Homo sapiens. Another humanoid species is called Homo habilis ("tool-using man"). Though wolves and the domesticated dog belong to the same genus, Canis, they are different species. The wolf is Canis lupus; the family pet is Canis familiarus.

Use a mushroom guide and other resources to answer these questions.

  1. What is the two-part scientific name for the common cultivated mushroom?

  2. Why are mushrooms raised in the dark?

  3. What is the scientific name for the common tomato? What is the scientific name for the white potato? The potato and the tomato both belong to what family?

  4. What do plants contain that allows them to make their own food? Do fungi have this facility? If not, then how do they make food?

  5. Why do you often find mushrooms and fungi in compost piles or on rotting tree stumps?


ANSWERS
  1. Agaricus bisporus

  2. They grow without light

  3. Lycopersicon esculentum; Solanum tuberosum; nightshade family

  4. Chlorophyll; no; from other organic matter

  5. They live off decaying remains




ACTIVITY 3: MAKE A SPORE PRINT

Mycologists (scientists who study mushrooms and other fungi) use spore prints to identify mushroom species. You can make a spore print, either from cultivated mushrooms bought at the supermarket or wild ones that grow in your yard after a rain.

PROCEDURE
  1. Choose a mushroom with a freshly opened cap (wild species work best).

  2. Cut off the stem close to the cap.

  3. Lay the cap, gills down, on a piece of paper. If the gills are white, use colored paper; if they're colored, use white paper.

  4. Cover the cap with a bowl and leave it for 24 to 36 hours.

  5. Remove the cover and carefully lift up the cap. You will see a radiating pattern of spores that have been released. You may want to preserve the print by spraying it lightly with clear fixative. Examine the spores more closely under a microscope.


NOTE: Wash your hands carefully with soap and water after handling wild mushrooms. Never eat any wild fungus or plant unless an expert has first identified it as being safe. Some people can gather wild mushrooms safely, but you should not try this unless accompanied by an expert.



MORE ABOUT MUSHROOMS

  • Mushroom recipes by Jack Czarnecki, the chef seen on Frontiers, can be found in Joe's Book of Mushroom Cookery (Atheneum, 1988).

  • For more information, contact one of the offices of the American Mushroom Institute: 907 East Baltimore Pike, Kennett Square, PA 19348; or, One Massachusetts Ave., NW, Suite 800, Washington, DC 20001. If you are traveling in the Brandywine area of Pennsylvania, visit the Mushroom Museum near Longwood Gardens, a few miles from Kennett Square (610-388-6082).

  1. What is the meaning of sclerotia, as referred to in the Frontiers story?

  2. One of the largest living organisms on earth belongs to the Fungi kingdom. A large honey mushroom patch, originating from a single spore, grows near Crystal Falls, Michigan. The mushroom, Armillaria bulbosa, is about 38 acres in size and is estimated to weigh more than 100 tons, about as much as a blue whale! What evidence might scientists use to prove that this giant fungus is actually a single organism?


ANSWERS
  1. Sclerotia refers to the hardened mycelium in fungi that remains dormant until a favorable opportunity for growth occurs; relate to other scientific words containing the root, sclero (hardness), as in multiple sclerosis.

  2. DNA analysis showed that the fungus in Michigan is a single organism; the ancient fungus may have been growing since the end of the last Ice Age.









 

Scientific American Frontiers
Fall 1990 to Spring 2000
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