Super-Powered ProtistsProtozoa are also known as protists. These are the bad boys of the microbe world (bad meaning "advanced"). Protists are eukaryotes with special structures that may be the base organisms of multicellular organisms. Meaning: they have structures that can be seen in advanced creatures and those structures are not seen anywhere else in the microbe world. You will also find the funkiest microbes in this category, such as the plasmodial slime molds. Actually, we just like saying "plasmodial". Mmmmm... Plasmodial.
Slime MoldsLet's start with the fun ones. Slime molds are not molds like a fungus. They sometimes act like a fungus, but they aren't. They are actually independent organisms. There are two big kinds of slime molds, cellular and acellular. Cellular slime molds are actually thousands of individual cells that team up and work together. They specialize for a short time and some do the eating, some work on reproduction, and some build special structures. When they are at the food source, they find it more efficient to work together.
Acellular slime molds might also be called plasmodial slime molds. Plasmodial slime molds are actually one cell. They can be huge, a couple of feet across, but still only one cell. They are able to grow so large because the one cell is multinucleated. That word means the cell has several nuclei inside. The plasmodial slime molds ooze across the ground of forests digesting everything they can. When it comes time to reproduce, they release all sorts of spores (like a fungus).
AmoebasAmoebas are easier to describe. You may have even seen these in your classrooms. They are small-single celled organisms that ooze from place to place. They reach out with one part of the cell, a structure called a pseudopod. They don't really have a shape because they are constantly on the move, hunting down food and eating by a process called phagocytosis. They wrap themselves around the food and absorb it into their body for digestion.
Identifying Microbes on the ISS (NASA eClips Video)