Domain Eukaryota |
| Famous from school biology classes, the amoeba form is one of the most common in nature. Not only does it occur in the Amoebozoa super--kingdom, but it appears in algae, fungi, plants and animals (in fact, human white blood cells are amoeboid). Most Amoebozoa are single-celled creatures that move with pseudopodia ("false feet") - finger-like protusions that pull the organism forward. They extrude these by internal cellular cytoplasmic flow. Some have flagella at some point. They have no definite shape, one or more nuclei and a flexible outer membrane. Amoebazoa are predators that hunt and eat bacteria. They feed by phagocytosis - they surround the bacteria and seal them into vacuoles for digestion and waste elimination. Many Amoebazoa form external cysts for protection when food is scarce or the environment harsh. These can travel by air to new locations. Amoebozoa are common in soils and aquatic habitats. Many are parasitic or symbiotic in other creatures, and some pathogenic. Amoebozoan cells vary greatly in size, from microscopic to big enough to see with the unaided eye. The Eumycetozoa, or ''Slime Molds' are multicellular and cover several square feet. The Amoebozoa are polyphyletic (the form appears repeatedly with no single common ancestor). The classification of the Amoebozoa is difficult, confusing and the subject of considerable genetic study. ----------------------------------------------------------------------------------------------------Amoebozoa: Uncertain Classification - Spongomonadida The Spongomonadida attach to surfaces and form branching colonies often covered with a mucus layer. They have one or two flagella. Originally placed in the Rhizaria super-kingdom, recent genetic studies align them with the Amoebozoa.
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