Fungi. Characteristics Eukaryotic. Primarily multicellular. Heterotrophic (saprobes). Cell wall...
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Transcript of Fungi. Characteristics Eukaryotic. Primarily multicellular. Heterotrophic (saprobes). Cell wall...
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.
Watch This!!!
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)
Watch This!!!
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).
• Watch This!!!
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.
Watch This!!!
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.