FUNGUSLIKE PROTISTS CHARACTERISTICS similar to fungi Appearance mode

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) • Scarcity of nutrients • cells aggregate → slimy mass →spore-bearing structure → amoeba-like cells

SLIME MOLDS • Phylum Myxomycota • Phylum Acrasiomycota

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

Physarum polycephalum

Physarum polycephalum

Comatricha typhoides

Lycolaga epinendrum “wolf’s milk”

Stemonitis splendens “chocolate tube slime”

Arcyris denudata “carnival candy slime”

Brefeldia maxima “tapioca slime”

Tubifera ferruginosa “red raspberry slime”

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.