Platyhelminthes are mostly worm like organisms that are dorsoventrally flattened, meaning they look like a leaf and this is why they are coined names like the Tapeworm, Flatworm, Fluke and Planarian.
Most Platyhelminthes are parasites on other animals but only the Turbellarians are mostly non-parasitic. A few species are commensalists, or mutualists living with other larger organism.
The myelin sheath covers most of the axon. It is important because it helps to protect the axon and speed up the neuron firing process by decreasing the amount of time in the axon.
