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Fungi

The Fungi Kingdom contains:

• Molds

• Mildews

• Rusts & Smuts

• Yeasts

• Mushrooms

Most fungi are saprophytic or parasitic

• They break down organic material returning nutrients to the soil.

• Yeasts are useful in the making of bread and fermented drinks.

• Human pathogens e.g. athlete's foot and ringworm.

|Fungi Body Parts: |[pic] |

|Hypha - the vegetative filament. | |

|Septum - perforated cross walls. | |

|Mycelium - a mat of interwoven hyphae. | |

| | |

|Fungi cell walls are made of chitin. | |

|Plant cell walls are made of cellulose. | |

 

Fungus life cycle:

Begins as a spore that grows when conditions are right.

Out of the spore wall grows a hypha.

The body of the fungus is made up of hyphal threads collectively called the mycelium.

The mycelium grows in soil or within dead wood or living organisms.

When growing conditions are favorable, the mycelium develops fruiting bodies, e.g. mushrooms.

Fruiting bodies produce new spores.

Types of reproduction: [pic]

[pic]Asexual:

• Forming spores at the end of the hyphe.

• Fragmentation- If the hyphe are broken, the pieces will grow into complete new organisms.

• Yeasts reproduce by an asexual process called budding. In this process, the yeast cell pinches itself off to produce a small offspring cell.

[pic]

[pic]Sexual:

• Each of the four divisions of fungi have different forms of sexual reproduction.

Fungi nutrition:

Heterotrophs – Fungi do not contain chlorophyll.

Saprotrophic - Decompose dead matter.

Parasitic - Obtain nutrients from living organisms.

Extracellular digestion by secreting enzymes into environment and absorbing the nutrients produced.

Fungi store their food as glycogen (like animals). Plants and green algae store their food as starch.

Fungi Classification, the Divisions (Phyla):

Zygomycota:

• Common bread mold

• Hyphae lack septa

• Asexual reproduction is by conjugation

Stinkhorn

Basidiomycota:

Mushrooms, puffballs, rusts, smuts, and stinkhorns

Underground hyphae intertwine and grow upward to produce a mushroom.

A "fairy ring" (shown below) is actually a single organism. As the hyphae expand outward, the mushrooms grow around the outer edge. As long as the organism survives, the circle of mushrooms will be wider every year.

Truffles

Downey Mildew

Mildew

Ascomycota:

• Mildews, yeasts, and truffles (sac fungi)

• The largest group of fungi

• Named for the reproductive sacs or Asci that form near the tips of the hyphae. Ascospores are formed here and released into the air when the ascus ruptures. These spores germinate to form new hyphae.

Yeast

Yeast (Candida)

Deuteromycota:

• Penicillium, ringworm, and athlete's foot (imperfect fungi)

• Sexual reproductive stage has not been observed.

 

[pic]

|Over 90% of plants have fungi associated with their roots. The fungus absorbs and concentrates phosphates for delivery to the plant roots. In |

|return, the fungus receives sugars synthesized by the plant during photosynthesis. |

| |

|Lichens: a symbiotic association between a fungus and a photosynthetic partner, usually green algae. |

|The fungi hyphae provide protection and hold moisture while the photosynthetic partner provides food. |

|[pic] |Upper Cortex: Short, thick hyphae pressed together to |

| |form a protective layer. |

| |  |

| |Photosynthetic Layer: In most lichens, the algae are |

| |found in a single layer under the protective cortex. |

| |  |

| |Pith: A loosely woven mat of hyphae holding moisture. |

| |  |

| |Lower Cortex: Just like the upper cortex protecting the|

| |bottom of the group. |

| |  |

| |Rhizomes: Bundles of hyphae anchoring the group. |

|Green color is because of the green algae cells growing between the hyphae of the fungus.|[pic] |[pic] |

| | | |

|The grey is a lichen | | |

|The orange is a fungus without algae | | |

 

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