We explain what an amoeba is and some characteristics of this genre of protists. In addition, their observations and approximate size.
What is an amoeba?
It is known as amoebas, amoebas or amoeba to a genus of unicellular protists, devoid of cell wall, which are characterized by their irregular shape and their movements based on pseudopods , that is, tentative extensions of their cytoplasm that allow them to phagocyte (encompass ) food and incorporate them through your cell membrane .
The amoebas are protozoa that inhabit the earth and water , where they feed on decomposing matter or smaller organisms, although some species have developed a parasitic life and require invading the internal systems of multicellular organisms, including the human being .
These are eukaryotic organisms, of different sizes, with a cell nucleus and a contractile vacuole and various minor vacuoles for digestive purposes. The simplicity of its structure and the versatility of its habits make the amoeba unicellular beings suitable for laboratory breeding and controlled experimentation. Initially they were cataloged within the animal kingdom, but in the new taxonomies of living beings they were assigned a taxonomic group of their own ( A moebozoa ) and assigned to the kingdom of the protists.
Its reproduction is asexual , binary fission and mitosis , and its feeding is heterotrophic, characterized by intracellular digestion. Its metabolism depends on the oxygen (cellular respiration) it takes through its membrane of the environment, just as it expels carbon dioxide and other undigested waste.
The amoebas were first observed in 1757 , by the German naturalist August Johann Rösel von Rosenhof. From its first observations of the changing form of the organism, the first species observed as Amoe b a proteus was baptized , referring to the name of the Greek god Proteus, capable of changing shape at will.
The usual size of amoebas is around 700/800 micrometers (μm), although larger species such as the Polychaos dubium (human parasite) reach a millimeter, being visible to the naked eye.