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Physarum polycephalum
Typically yellow in color, this eukaryotic microbe eats fungal spores, bacteria, and other microbes. P. polycephalum has been used as a model organism for many studies involving amoeboid movement and cell motility. The plasmodium consists of networks of protoplasmic veins, and many nuclei. It is during this stage that the organism searches for food. The plasmodium surrounds its food and secretes enzymes to digest it.
Spotted on a log in a wetland habitat at Dash Point State Park.
If environmental conditions cause the plasmodium to desiccate during feeding or migration, Physarum will form a sclerotium. The sclerotium is basically hardened multinucleated tissue that serves as a dormant stage, protecting Physarum for long periods of time. Once favorable conditions resume, the plasmodium reappears to continue its quest for food. As the food supply runs out, the plasmodium stops feeding and begins its reproductive phase. Stalks of sporangia form from the plasmodium; it is within these structures that meiosis occurs and spores are formed. Sporangia are usually formed in the open so that the spores they release will be spread by wind currents. Spores can remain dormant for years if need be. However, when environmental conditions are favorable for growth, the spores germinate and release either flagellated or amoeboid swarm cells (motile stage); the swarm cells then fuse together to form a new plasmodium.- Wikipedia.
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