Tetrahymena
| Tetrahymena | ||||||||||||
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Tetrahymena thermophila |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Tetrahymena | ||||||||||||
| Furgason , 1940 |
Tetrahymena is a genus of eukaryotic unicellular organisms thatbelongs tothe ciliate tribe. Species of this genus occur in seas, fresh water and moist soil. Due to the special characteristics of their mouth system, they arecounted amongthe Hymenostomatida (Gr. For 'skin mouths').
construction
The species of the genus Tetrahymena are 30 to 60 μm in size and covered on all sides by a holotric ciliature . This means that the whole body is covered with eyelashes, which explains their generic name ciliate (from cilia = eyelashes). The ciliary body is used for locomotion and is extremely sensitive to sensory (sensory) stimuli. The organism has the same oral apparatus (cell mouth, cytostome ) as the paramecium , which clearly occupies a quarter of the front side. Visible under the microscope are the four small membranes laid out in parallel and covered by cilia, which mark the mouth. The Tetrahymena owe their name to this structure (Greek: tetra- = 'four').
Like other ciliates, this genus also has the cytoproct (or cell auger ) required for excretion . Tetrahymena species have the typical features of a eukaryotic cell, such as endoplasmic reticulum , lysosome and ribosome .
Genetic characteristics
The genetic peculiarity that characterizes the genus Tetrahymena as it does for all ciliate animals is the nuclear dimorphism . The organisms each have a micro- and a macronucleus. While the DNA sits in the diploid micronucleus , the macronucleus contains the rearranged RNA interference (RNAi).
Individual evidence
- ↑ Lexicon of Biology in eight volumes, fourth volume, Breisgau: Verlag Herder Freiburg, 1985
- ↑ Eric S. Cole: The Tetrahymena Conjugation Junction. National Center for Biotechnology Information, US National Library of Medicine, accessed October 21, 2013 .
- ↑ Diethard Baron (ed.): Green series. Materials for Upper Secondary Education - 2004 Edition: Genetics. School volume: materials S II. Schrödel, Braunschweig 2004 ISBN 3-507-10910-7
Web links
Paramecium (2007) | Tetrahymena (2009) | Eye animals (2010) | Dictyostelium (2011) | Acanthamoeba (2012) | Actinophrys (2013) | Trumpet Animals (2014) | Vampire Amoeba (2015) | Trichomonas (2016) | Diaphanoeca grandis (2017) | Dictyocysta mitra (2018) | Nuclearia (2019)