Planarians


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Planarians

 

a group of invertebrates of the suborder Tri-cladida of the class Turbellaria. Planarians are quite large, reaching a length of 35 cm. They are distributed throughout the world. The worms live in freshwaters and, less frequently, in seas; in the tropics they are also found in the soil. They feed on small invertebrates. Fishes do not eat planarians because the skin contains poison glands.

References in periodicals archive ?
The ability to follow individual neoblasts opens the door to uncovering the molecular cues that help planarian stem cells navigate to the site of injury and ultimately may allow scientists to provide therapeutic stem cells with guideposts to their correct destination.
He pinpointed the locations of stem cells and studied how far they dispersed using RNA whole-mount in situ hybridization (WISH), specifically adapted to planarians in Sanchez Alvarado's lab.
In this study, our main interest was to demonstrate the high level of neurobiological development of the Onychophora, as shown by the presence of cephalic ganglion, well-differentiated neurons characterized by a high production of synaptic vesicles, and having a proportionality of their cytoplasm and nucleus very much similar to that of planarian neurons (Reuter 1981, Biserova et al.
Exotic land planarians of the genus Bipalium (Platyhelminthes: Turbellaria) from Pennsylvania and the Academy of Natural Sciences, Philadelphia.
Planarians are generally intolerant of organic pollution, although some species have been observed in heavily polluted waters (Kenk 1974).
Fissiparity is a frequent and interesting mode of asexual reproduction that is widespread in freshwater planarians that have no sexual apparatus; hence the term, fissiparous.
Planarians reportedly avoid a solution prepared by pulverizing a conspecific in 1 ml of water (the full-strength test solution).
Planarians get smaller when there is no food, and they return to their original size when feeding is reinstated.
Using complementary methods, Reddien and graduate students Dan Wagner and Irving Wang demonstrated that adult planarians not only possess pluripotent stem cells known as clonogenic neoblasts (cNeoblasts), a single such cell is capable of regenerating an entire animal.
Planarians are famous for their immense power of regeneration, being able to regenerate a new head after decapitation.