Platyhelminthes Platyhelminthes is a Flatworm. The meaning of Platy is flat, and the meaning of helminthes is a worm. So it`s very straight forward what the meaning Platyhelminthes is. Flatworms are very simple animals with bilateral symmetry. Flatworms are only a few mm. thick, but can be up to 20 m. long! They have one or more pairs of eyes and sensitive organs called ocelli. The eyes don`t see objects, but instead they detect light or darkness to they`re environment.
A typical environment for a flatworm to found in would be streams, lakes, and oceans. Flatworms can be carnivores and eat small aquatic animals, or can be scavengers eating dead things. At the end of a mascular tube on a flatworm it`s called a Pharynx, the pharynx seeks food into the gastrovacular cavity. The cavity forms an intestine with many branches along the entire length of the worm. Inside the intestines, enzymes help break down food into smaller particles.
Digestion is completed inside the intestinal wall. Flatworms are also very sensitive to chemicals found in their food and the water it swims in its environment. Flatworms use two locomotion’s which are cilia and their epidermal cells, help them glide through water over the bottom of the sea and they use muscle cells that are controlled by the nervous system allowing to twist and turn their body reacting to their environmental conditions.
Most flatworms are hermaphrodrodites (male & female). Flatworms can also reproduce asexually and sexually. A flatworm can reproduce very simply by falling into pieces and each fragment would form a new flatworm. Flatworms reproduce sexually by having one flatworm give sperm to the other. The flatworm would lay eggs in small clusters. The eggs would hatch in just a few weeks.