What are the three main classes of flatworms?
The Phylum: Platyhelminthes includes the flatworms (Planaria, flukes & tapeworms) Three Classes treated here are Turbellaria, Trematoda and Cestoda.
What are the two major groups of flatworms?
They are ribbon-shaped and are flattened dorsoventrally. There are four major classes of flatworms such as Cestoda (tapeworms), Turbellaria (planarians), Trematoda (flukes), and Monogenea. The class Turbellaria (planarians) is free-living.
What are the major classes of platyhelminthes?
The Platyhelminthes includes three classes: the Turbellaria (free-living flatworms), the Trematoda (flukes), and the Cestoda (tapeworms).
Which are the two main classes of platyhelminthes give few characteristics of them?
Platyhelminthes have the following important characteristics:
- They are triploblastic, acoelomate, and bilaterally symmetrical.
- They may be free-living or parasites.
- The body has a soft covering with or without cilia.
- Their body is dorsoventrally flattened without any segments and appears like a leaf.
What is unique about Planarians?
Planaria exhibit an extraordinary ability to regenerate lost body parts. For example, a planarian split lengthwise or crosswise will regenerate into two separate individuals. Some planarian species have two eye-spots (also known as ocelli) that can detect the intensity of light, while others have several eye-spots.
Do Planarians prefer light or dark?
First, planarians have bilateral symmetry with two nerves extending the length of the body, an enlarged “brain” (ganglion cell), and two eye spots. The eye spots are sensitive to light. Planarians move away from the light and are most active in the dark.
How big do Planaria get?
Planarians are usually about 3 to 15 mm (0.1 to 0.6 inch) long; however, some grow to more than 30 cm (about 1 foot) long.
Are Planarians dangerous to humans?
While they pose no danger to humans or plants, Land Planarians have been labeled a nuisance in the southern United States in particular, and have been known to decimate earthworm populations in farms and earthworm rearing beds.
Are Bipalium poisonous?
Toxicity. Bipalium kewense is one of the few terrestrial invertebrates known to produce tetrodotoxin, a neurotoxin that results in paralysis. It is possible that the toxin aids the planarian in subduing its prey as well as in protecting it against predators.