Free-living Flatworm
Turbellaria
Summary 2
The Turbellaria are one of the traditional sub-divisions of the phylum Platyhelminthes (flatworms), and include all the sub-groups that are not exclusively parasitic. There are about 4,500 species, which range from 1 mm (0.039 in) to 600 mm (24 in) in length. All the larger forms are flat with ribbon-like or leaf-like shapes, since their lack of respiratory and circulatory systems means that they have to rely on diffusion for internal transport of metabolites. However, many of the smaller forms...
Fuentes y créditos
- (c) Richard Ling, algunos derechos reservados (CC BY-NC-SA), http://www.flickr.com/photos/82825649@N00/438039243
- (c) Wikipedia, algunos derechos reservados (CC BY-SA), http://en.wikipedia.org/wiki/Turbellaria
