190 likes | 458 Views
FUNGI. Fungi Characteristics. Multicellular heterotrophic eukaryotes (Saprobes ) Saprobes help absorb food from decaying matter (NO photosynthesis) Always make spores (haploid) If a spore germinates, it produces hyphae, a network of fine filaments. Mycelium – make from hyphae, used to
E N D
Fungi Characteristics • Multicellular heterotrophic eukaryotes (Saprobes) • Saprobes help absorb food from decaying matter (NO photosynthesis) • Always make spores (haploid) • If a spore germinates, it produces hyphae, a network of fine filaments. • Mycelium – make from hyphae, used to absorb nutrients Contain ½ the DNA to make fertile offspring
Fungi Characteristics Cont’d… 1mm2 Eukaryotes with cell walls, but no cellulose Importance – decomposers, food, drugs May cause disease – Athlete’s foot, Amanita (deadly mushroom)
Fungi are Classified by Reproduction: 1. Division Zygomycota • Spores carried by air in case-like sporangium • Rhizopussp. (common bread mould) - hyphae (called rhizoids) extend into food source and absorb nutrients
During unfavourable conditions dormant zygospores form from the mating of 2 opposite strains of hyphae and germinate when conditions improve.
2. Division Ascomycota (Sac Fungi) • Spores carried in sac-likestructures (ascus)
Sacklike Fungi Examples Mildew • Powdery mildews • Parasitic ascocarps • Infect cereals, roses and other crops
More Saclike Fungi … • Yeast • Unicellular • Usually reproduce by budding (asexual) • Can form ascus under poor conditions (sexual) • Often parasitic • Ex. Apple scab
More Saclike fungi... • Penicillum sp. • 1928 Sir Alexander Fleming discovered a chemical substance produced by fungi that inhibited growth of bacteria • "Penicillin" became the first antibiotic
3. Division Basidiomycota • Spores form in a clublikemass of hyphae to absorb water. • Fruiting body - structure above ground • Cap - umbrella-like structure, produces spores • Gills - contains reproductive basidia cells , each with 1000’s of spores
Cap Hyphae
Lichens Fungi living with alga or cyanobacteria Algae provides nutrients Fungi provides water, minerals, protection Mycorrhizae Fungi that live in roots of plants Better plant resistance to drought Symbiotic Associations:
Work: • Complete dichotomous key activity from last day. • Read