Phylum Zygomycota

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Phylum Zygomycota
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General Characteristics

• They produce a special type of thick walled
  spore, which develop from zygotes during sexual
  reproduction.
• They are mostly saprobic, but some are parasitic,
  living on plants, insects, and other fungi.

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Structure of Bread Mold

• The white/grey mycelium consists of several kinds
  of hyphae
• Root like hyphae which anchors mold,
  secretes digestive enzymes, and absorbs
  nutrients. These are called rhizoids
• Stolons which grow over the surface of the
  food.
• Sporangiophores grow up from the stolons.
  At the tip of each is a round spore case called a
  sporangium.

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ChitinWhy So Important?

• Chitin is the substance found in the cell walls
  of fungi.
• It shimmers, and has a crystalline appearance.
• It is important in making the fungus resistant to
  dryness, and makes it more durable because of its
  strength.

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Reproduction of Bread Mold

• Large numbers of spores form in each sporangium.
• When the case opens at maturity, the spores are
  released.
• If they land in favourable environments, they
  will germinate and form a new mycelium.

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Sexual Reproduction

• Sexual reproduction occurs through conjugation.
• Here, different strains of hyphae touch each
  other, and form a hardened zygospore, that can
  survive harsh conditions
• Inside, the and nuclei will have joined to
  form a new diploid nuclei.
• If conditions are favourable, the zygospore will
  germinate.
• Upon meiosis, only one haploid nucleus remains,
  as the other three will degenerate.
• The new haploid cell, will then give rise to a
  sporangiophore, which will go on to reproduce
  asexually.

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