They produce extensive mycelia, some of which become modified to form gamete-producing structures. The diploid zygote develops into a resting spore that will germinate into a mycelium-producing motile, asexual spores. The cells are phagocytic and can aggregate to form a slimy mass that can migrate to find new food sources. Slime molds also disperse by spores released from stalk-like structures. Phylum Myxomycota is the designation for the plasmodial slime molds, which move as large masses of aggregated cells.
Protozoans are all single-celled and heterotrophic.
Protozoan Life Cycles Asexual reproduction by fission or budding dominates protozoan life cycles. Many form resistant cysts. A few protozoans are famous for the diseases they cause in humans. The amoebas include Amoeba proteus , seen by students in biology laboratories, and Entamoeba , the cause of a severe form of dysentery. The radiolarians resemble heliozoans in shape but have delicate shells of silica.