Planarians have simple organ systems and lack respiratory and circulatory systems.
Flame cells remove unwanted liquids from the body by passing them through ducts that lead to excretory pores where the waste is released on the dorsal surface of the planarian.
Planarians are globally distributed and common to many parts of the world, residing in freshwater ponds and rivers.
Systematists have traditionally recognized three major groups of triclads: Paludicola (freshwater planarians), Maricola (marine planarians), and Terricola (land planarians), but some propose a fourth planarian infraorder Cavernicola (Carranza et al.
Planarians receive oxygen and release carbon dioxide by diffusion.
Planarians move by beating cilia on the ventral surface, allowing it to glide along on a film of mucus.
Other common varieties are the blackish Planaria maculata and Dugesia dorotocephala.
Planarians or triclads are widely distributed, common, and diverse.
At the heart of modern Ankara is Atatьrk's mausoleum, An?tkabir.
The most frequently used planarians in high schools and first-year college laboratories are the brownish Dugesia tigrina.
A planarian is any flatworm (phylum Platyhelminthes) of the suborder (or order) Tricladida of the class Turbellaria.
Planarians range in size from about 3 to 12 mm.
A planarian can reproduce either asexually or sexually, with sexual reproduction being most common.
Planarians are common organisms for scientific research and classroom teaching.
In asexual reproduction, the planarian anchors its tail end, then detaches its tail end from the anterior portion (the rupture line is posterior to the mouth, with each half regrowing the lost parts.
Some planarians have achieved pest status as a result of being invasive species.
The term "Polynesia" was coined by Charles de Brosses in 1756, and originally applied to all the islands of the Pacific.
The intestines of the planarian branch throughout the body.
Primarily free-living, planarians are characterized by a soft, broad, leaf-shaped (when elongated) body with cilia and a three-branched digestive tract (as reflected in the name Tricladida).