Amoeba – Concept, reproduction and size

We explain what an amoeba is and some characteristics of this genus of protists. Also, your observations and approximate size.

Amoebas are protozoa that inhabit land and water.

What is an amoeba?

It is known as amoebas, amoebas or amoebas to a genus of unicellular protists, lacking a cell wall, which are characterized by their irregular shape and their movements based on pseudopods, that is, of tentacular extensions of its cytoplasm that allow it to engulf (engulf) food and incorporate them through its cell membrane.

Amoebas they are protozoa that inhabit land and water, where they feed on decomposing matter or smaller organisms, although some species have developed a parasitic life and require to invade the internal systems of multicellular organisms, including humans.

They are eukaryotic organisms of varying size, with a cell nucleus and a contractile vacuole and various minor vacuoles for digestive purposes. The simplicity of their structure and the versatility of their habits make amoebae the ideal unicellular beings for laboratory breeding and controlled experimentation. Initially they were cataloged within the kingdom of animals, but in the new taxonomies of living beings they were assigned their own taxonomic group (TOmoebozoa) and were assigned to the kingdom of the protists.

Its reproduction is asexual, by binary fission and mitosis, and their diet is heterotrophic, characterized by intracellular digestion. Its metabolism depends on the oxygen (cellular respiration) it takes in through its membrane from the environment, in the same way that it expels carbon dioxide and other undigested waste.

Amoebas were first observed in 1757, by the German naturalist August Johann Rösel von Rosenhof. From his first observations of the changing shape of the organism, the first observed species was named Amoebto proteus, alluding to the name of the Greek god Proteus, capable of changing shape at will.

The usual size of amoebae is around 700/800 micrometers (μm), although larger species such as Polychaos dubium
(parasite of the human being) reaches to measure a millimeter, being visible to the naked eye.