Fungi. Characteristics Eukaryotic. Primarily multicellular. Heterotrophic (saprobes). Cell wall contains chitin. Body of multicellular fungi composed.

Fungi

Characteristics

• Eukaryotic.• Primarily multicellular.• Heterotrophic (saprobes).• Cell wall contains chitin.• Body of multicellular

fungi composed of hyphae.• Sexual and asexual

reproduction.

Characteristics

• Hyphae grows into a mass called a mycelium.

• Mycelium absorbs nutrients from food.

Classification

Fungi are grouped into divisions based on their pattern of sexual reproduction.

Classification

• Division Zygomycota– Spores in a case-like structure (sporangium).

• Division Ascomycota– Spores in a sac-like structure (ascus).

• Division Basidiomycota– Spores in a club-like structure (basidium).

* Spores are the haploid reproductive cells.

Case-like Fungi(Division Zygomycota)

• Example: Bread mould (Rhizopus)

Bread Mould (Rhizopus)

Asexual Reproduction• Hyphae extends along surface and into food.

– Absorb water and sugar.

• Black sporangia form.– Each contains

thousands of spores.

– Spores dispersed via wind.

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Bread Mould (Rhizopus)

Sexual Reproduction

• Occurs under less favourable conditions.

• Two genetically different hyphae are produced.– Upon contact a zygospore forms.– Remains dormant until conditions improve.

Bread mould (Rhizopus)

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Sac-like Fungi(Division Ascomycota)

• Example: Mildews, some moulds and yeasts

Penicillium

• Alexander Fleming discovered that a chemical released by Penicillium inhibited bacterial growth.

• First antibiotic (penicillin).

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Yeasts

• Unicellular.

• Under favourable conditions asexual reproduction occurs rapidly via budding.

• Under less favourable conditions sexual reproduction forms ascospores.– Remains dormant until conditions improve.

Yeasts

Applications

• Anaerobic respiration (fermentation)– Carbon dioxide and ethanol released as

byproducts.– Used in the bread and alcohol industry.

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Club-like Fungi(Division Basidiomycota)

– Puffballs– Bracket fungi

• Examples:

– Mushrooms

– Rusts

Gilled Mushrooms

• Umbrella-shaped cap.– Gills (lamellae) on underside.– Each gill contains thousands of basidia.– Each basidium contains

thousands of spores.

– Dispersed by wind.

Gilled Mushrooms

“Imperfect” Fungi

• No known sexual phases.• Example:Trichophyton

rubrum– Causes athlete’s foot.– Lives in warm, damp places

(floors of showers and pools).– Symptoms: reddened,

cracked and peeling skin; itching, burning and stinging.

Fungal Associations

Lichens

Mycorrhizae

HOMEWORK: in a couple sentences, describe the symbiotic relationships listed above.