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FUNGUS-LIKE PROTISTS. CHARACTERISTICS. similar to fungi Appearance mode of nutrition non-photosynthetic life cycle mold-like and Ameba-like. SLIME Molds. Dominant stage: amoeba-like cells (phagocytic) near rich sources of food (e.g. rotting wood, piles of compost, thick wet lawns)
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CHARACTERISTICS • similar to fungi • Appearance • mode of nutrition • non-photosynthetic • life cycle • mold-like and Ameba-like
SLIME Molds • Dominant stage: • amoeba-like cells (phagocytic) • near rich sources of food • (e.g. rotting wood, piles of compost, thick wet lawns) • Scarcity of nutrients • cells aggregate → slimy mass →spore-bearing structure → amoeba-like cells
Phylum Myxomycota Phylum Acrasiomycota SLIME MOLDS
Phylum Myxomycota • acellular or plasmodial slime molds • Plasmodium • large cytoplasmic mass (multinucleate) • feeding stage • forms spores • Unfavorable conditions: “fruiting” • spore-bearing • haploid spores (meiosis)
Phylum Myxomycota • spores → flagellated gametes →diploid zygote (sexual reproduction) →*diploid amoeboid cells • e.g. Physarum
Phylum Acrasiomycota • cellular slime molds • pseudoplasmodium • separated by cell membranes • Cell aggregation • slug-like form • migrates to form fruiting body • spores by mitosis
Phylum Acrasiomycota • reproduction is asexual • e.g. Dictyostelium discoideum
DEVELOPMENTAL STAGES OF A CELLULAR SLIME MOLD DIctyostelium sp.