''Amoeba proteus'' is a large species of

amoeba An amoeba (; less commonly spelled ameba or amœba; plural ''am(o)ebas'' or ''am(o)ebae'' ), often called an amoeboid, is a type of cell or unicellular organism with the ability to alter its shape, primarily by extending and retracting pseudop ...

closely related to another genus of giant amoebae, '' Chaos''. As such, the species is sometimes given the alternative scientific name ''Chaos diffluens''. Amoeba proteus locomotive form

This protozoan uses extensions called

pseudopodia A pseudopod or pseudopodium (plural: pseudopods or pseudopodia) is a temporary arm-like projection of a eukaryotic cell membrane that is emerged in the direction of movement. Filled with cytoplasm, pseudopodia primarily consist of actin filament ...

to move and to eat smaller unicellular organisms. Food is enveloped inside the cell's

cytoplasm In cell biology, the cytoplasm is all of the material within a eukaryotic cell, enclosed by the cell membrane, except for the cell nucleus. The material inside the nucleus and contained within the nuclear membrane is termed the nucleoplasm. ...

in a food

vacuole A vacuole () is a membrane-bound organelle which is present in plant and fungal cells and some protist, animal, and bacterial cells. Vacuoles are essentially enclosed compartments which are filled with water containing inorganic and organic m ...

, where ingested matter is slowly broken down by enzymes. ''A. proteus'' inhabits freshwater environments and feeds on protozoans, algae, rotifers, and even other smaller amoebae. They are colorless, but they may have colored inclusions derived from its food. ''A. proteus'' possesses a thick-walled

nucleus Nucleus ( : nuclei) is a Latin word for the seed inside a fruit. It most often refers to: * Atomic nucleus, the very dense central region of an atom *Cell nucleus, a central organelle of a eukaryotic cell, containing most of the cell's DNA Nucl ...

containing granular

chromatin Chromatin is a complex of DNA and protein found in eukaryote, eukaryotic cells. The primary function is to package long DNA molecules into more compact, denser structures. This prevents the strands from becoming tangled and also plays important ...

, and is therefore a

eukaryote Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacter ...

. Its

membrane A membrane is a selective barrier; it allows some things to pass through but stops others. Such things may be molecules, ions, or other small particles. Membranes can be generally classified into synthetic membranes and biological membranes. ...

includes a phospholipid bilayer similar to other eukaryotic organisms.

History

The first description of this amoeba is probably that of August Johann Rösel von Rosenhof who, in 1755, published drawings of an amoeboid protozoan he called the "little Proteus". Subsequently, various authors assigned Rösel's organism and other amoeboid protozoa various names:

Carl Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, ...

termed Rösel's organism ''Chaos protheus'' in 1758.

Otto Friedrich Müller Otto Friedrich Müller, also known as Otto Friedrich Mueller (2 November 1730 – 26 December 1784) was a Danish naturalist and scientific illustrator. Biography Müller was born in Copenhagen. He was educated for the church, became tutor to a ...

referred to it as ''Proteus diffluens'' in 1786. In 1878,

Joseph Leidy Joseph Mellick Leidy (September 9, 1823 – April 30, 1891) was an American paleontologist, parasitologist and anatomist. Leidy was professor of anatomy at the University of Pennsylvania, later was a professor of natural history at Swarthmore ...

proposed the current name ''Amoeba proteus'' to describe Rösel's ''Proteus'', ''Proteus diffluens'', and another described amoeba ''Amoeba princeps''.

Reproduction

Although ''Amoeba proteus'' has most of the key proteins associated with sexual processes (as do other amoebae), no evidence of meiosis or sexual activity has been reported.

Video gallery

References

Tubulinea Articles containing video clips Taxa named by Peter Simon Pallas Taxa named by Joseph Leidy {{Amoebozoa-stub

History

Reproduction

Video gallery

See also

References