Anatomy
The cell's organelles and cytoplasm are enclosed by a cell membrane; it obtains its food through phagocytosis. This makes amoebae heterotrophs. Amoebae have a single large tubular pseudopod at the anterior end, and several secondary ones branching to the sides. The cytoplasm of amoeba is divided into outer ectoplasm and inner endoplasm.The most famous species, Amoeba proteus, averages about 220-740 μm in length while in motion, making it a giant among amoeboids. A few amoeboids belonging to different genera can grow larger, however, such as Gromia, Pelomyxa, and Chaos.
Amoebae's most recognizable features include one or more nuclei and a simple contractile vacuole to maintain osmotic equilibrium - low water amounts in cell protecting cell from bursting with excess water. Food enveloped by the amoeba is stored and digested in vacuoles. Amoebae, like other unicellular eukaryotic organisms, reproduce asexually via mitosis and cytokinesis, not to be confused with binary fission, which is how prokaryotes (bacteria) reproduce. In cases where the amoeba are forcibly divided, the portion that retains the nucleus will survive and form a new cell and cytoplasm, while the other portion dies. Amoebae also have no definite shape.
Read more about this topic: Amoeba
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—Ralph Waldo Emerson (1803–1882)
“Man is a shrewd inventor, and is ever taking the hint of a new machine from his own structure, adapting some secret of his own anatomy in iron, wood, and leather, to some required function in the work of the world.”
—Ralph Waldo Emerson (1803–1882)
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