Planaria
Planaria sp., or cross-eyed worm, is a common freshwater flatworm. It moves by cilia on the ventral dermis, allowing it to glide along on a film of mucus. Planaria have 2 eyespots that act as photoreceptors. Being light sensitive they shy away from light. Some move by undulations of the whole body by the contractions of muscles built into the body wall. Planaria are a member of the class Turbellaria and the phylum of flatworms, Platyhelminthes. They exibit an extraordinary ability to regenerate lost body parts. The size ranges from 3 to 12mm and the body has two eye-spots (also known ocilli), used to move away from light sources. For example, a Planaria split length wise or crosswise will regenerate into 2 separate individuals.
Planaria are common to many parts of the world and reside in fresh water ponds.
The most frequently used in the laboratory is the brownish Dugesia tigrina. Other common varieties are the blackish Planaria maculata and Planaria dorotocephalia.
This article is a stub. You can help BambooWeb by .
U suk******************************************************************************************************************************************8
