MOST FUNGI ARE DECOMPOSERS

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MOST FUNGI ARE DECOMPOSERS

• FUNGI ABSORB MATERIALS FROM THE ENVIRONMENT
• INCLUDE MUSHROOMS, MOLDS, YEAST
• CAN BE HELPFUL OR HARMFUL TO OTHER ORGANISMS

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Absorb Material from Environ.

• Typical fungus made of reproductive body
  network of cells forming threadlike hyphae (one
  cell thick). A mass of hyphae form a mycelium.
  The cells release chemicals, digesting
  surrounding materials absorbing nutrients.
• Fungi reproduce sexually (with spores) or
  asexually. Spore one reproductive cell that can
  grow into new fungus.

• Most are decomposers that absorb nutrients
  leave behind simpler compounds.
• Are heterotrophs (get energy from living or once
  living matter).
• They and bacteria decompose leaves, shed skin,
  animal droppings, etc.
• Except for yeast, most fungi are multicellular.

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Absorb Material from Environ.

• A single mushroom can make a billion spores.
• Spores are released into air spread by wind
  long distances.
• Some spore have tough coverings protecting them
  for years until conditions are right for growing.
• Fungi can reproduce asexually when hyphae break
  off to form anew mycelium. Yeast (single cell
  fungi) reproduce by cell division, budding
  spores.

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Mushrooms, Molds Yeast

• One mushroom may be from a mycelium that fills
  the size of a football field.
• Some mushrooms are poisonous some edible. The
  cap is where spores are made, and hyphae fill the
  cap stalk.
• MOLDS fuzzy growth sometimes seen on food
  hyphae grow into food digest it as they grow.
• Some Penicillium mold are used in Brie blue
  cheese. Some aspergillus mold is used in soy
  sauce. Trichoderma mold grows in soil makes
  digestive chemicals used to give blue jeans a
  stonewashed look.

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Mushrooms, Mold, Yeast

• Molds may cause disease. Fungal molds cause
  athletes foot others affect plants (Dutch elm)
  Penicillin is an antibiotic from Penicillium
  fungus.
• Molds reproduce via spores mostly carried by air
  the hat thrower fungus Pilobolus grows in
  animal droppings shoots off its spore cap via
  water pressure to land a few feet away to
  hopefully be eaten in the grass by a cow.

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Mushrooms, Molds Yeast

• Yeasts are single celled fungi. Grow in moist
  environments (plant sap, skin, shower curtains)
• If yeast growing on human skin reproduces too
  rapidly, it may cause disease.
• Used in food products (breaks down sugars making
  CO2 gas to make bread rise give wine/beer its
  bubbles).

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Fungi can be Helpful or Harmful

• Fungi bacteria are Earths decomposers (even
  live in sea to recycle materials for ocean-living
  organisms).
• Hyphae grow into decompose other organisms
  material (to turn dead tree back into useful
  nutrient rich soil or to kill off Dutch elm)
• Most hyphae surround plant roots providing
  nutrients for plant, while plant provides food.
• Lichen fungal hyphae mixed around single celled
  algae. Lichen live in arctic desert, even bare
  rock, eventually breaking it down into soil.

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Helpful/Harmful Fungi

• May make toxins (In 1845 fungus infected
  Irelands potato crop, dropping causing Ireland
  to go from 8 million to 4 million people many
  died of disease, starvation and others left, many
  to US. Today, many banana crops are being
  destroyed by fungal disease.
• Penicillin from a fungal toxin kills off many
  types of bacteria, so is used as an antibiotic.