Fungi

Characteristics Eukaryotic. Primarily multicellular. Heterotrophic (saprobes). Cell wall contains chitin. Body of multicellular fungi composed of hyphae. Sexual and asexual reproduction. Release digestive enzymes into the environment. Digested organic matter absorbed through the cell wall.

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 Division Ascomycota 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) Phylum = division

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 Phylum = division

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) Examples: Mushrooms Rusts Puffballs Bracket fungi Phylum = division

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.