- Turritopsis nutricula
Taxobox
name = "Turritopsis nutricula"
image_width = 240px
regnum =Animal ia
phylum =Cnidaria
classis =Hydrozoa
ordo =Hydroida
familia =Clavidae
genus = "Turritopsis "
species = "T. nutricula"
binomial = "Turritopsis nutricula"
binomial_authority =McCrady , 1858"Turritopsis nutricula" is a
hydrozoa n with a life cycle in which it reverts back to thepolyp stage after becoming sexually mature. It is the only known case of a metazoan capable of reverting completely to a sexually immature, colonial stage after having reached sexual maturity as a solitary stage Harv|Piraino|Boero|Aeschbach|Schmid|1996|p=302. It does this through the cell development process oftransdifferentiation . Theoretically, this cycle can repeat indefinitely, rendering it effectively immortal.Description
"Turritopsis nutricula" has a diameter of 4-5 millimeters. It has an equally high and bell-shaped figure. The walls are uniformly thin. The bright red, big stomach has a cruciform shape in its cross section. Young specimens have only eight tentacles along the edge, while adult specimens have 80-90 tentacles.
Life cycle
The fertilized eggs develop in the stomach and in the screen formed by the cave in the jellyfish Planula. The eggs are then planted on the seabed in polyp colonies. The jellyfish hatches after two days. The jellyfish becomes sexually mature after a few weeks (the exact duration depends on the ocean temperature; at 20°C it is 25 to 30 days and at 22°C it is 18 to 22 days).
Immortality
Jellyfish usually die after propagating, however the "Turritopsis nutricula" has developed the ability to return to a polyp state. This is done through a cell change in the external screen (Exumbrella). The ability to reverse the life cycle is unique in the animal kingdom, and allows the jellyfish to bypass death, rendering the "Turritopsis nutricula" immortal.
pread
"Turritopsis nutricula" are found in temperate to tropical regions in all of the world's oceans.
References
* [http://8e.devbio.com/preview_article.php?ch=2&id=6 Cheating Death: The Immortal Life Cycle of "Turritopsis"]
*
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