slime mold Any of various organisms that exist as slimy masses and are commonly found on decaying plant matter. They are classified among the protists as two distinct phyla, Dictyolsteliomycota (the cellular slime molds) and Myxomycota (the plasmodial slime molds). The two phyla are not directly related to each other. ◇ Cellular slime molds live as single, amoeba-like cells moving about feeding on bacteria. When food becomes scarce, they combine into a large, slug-like, mobile colony. This migrates to a new area before developing into a multicellular stalked structure that produces and releases spores. Each spore then develops into a new amoeba-like cell. ◇ Plasmodial slime molds exist as a mass of amoeba-like protoplasm (called a plasmodium) that contains many nuclei within a single cell membrane. A single organism can spread out thinly and cover up to several square meters. The slimy mass moves along ingesting bacteria, fungi, and other organic matter. When food grows scarce, they stop moving and grow multicellular, spore-producing stalks. The plasmodial slime molds are also called myxomycetes. |