echinodermata
The echinoderm is of the Phylum Echinodermata, which is a phylum of marine animals. This Phylum includes about 70,000 living species such as sea stars, sea urchins, sand dollars, and sea cucumbers. This makes the Echinodermata the largest phylum that has no freshwater of terrestrial representatives.
sea urchin (disambiguation)
Sea urchins eat using these five sharp wedges that come together like a beak and that are moved by muscles. This beak allows the urchin to scrape algae off the reef coral and rocks. Its then swept into the mouth by its tube feet. Its mouth is on the bottom and anus on top of the creature. Once inside the mouth, it is passed to the esophagus. After being passed through the esophagus, food is sent to the long, winding intestines where it is digested. Waste is then sent out the top side through the anus.
starfish (asterozoa)
The mouth of the sea star is found on the under side of the creature. Food enters the mouth and into the first stomach. Then it is passed onto the secondary stomach and then into the many digestive glands that are located within each of the arms of the sea star. These digestive glands secrete enzymes and absorb the nutrients from food. A small intestine runs from the secondary stomach to the external port which is located in the upper part of the body. Some species of Starfish eat their prey whole and begin digesting it before sending it to the digestive glands in the arms. Other species are able to put their stomach outside their bodies, where it can eat food and begin the digestion process. It passes this food to its secondary stomach, which always stays inside the Starfish. Further digestion occurs at the intestine. Finally, waste is excreted through the anus on its aboral side of the body.
sea cucumber (holothuroidea)
Sea cucumbers are scavengers that feed on debris on the floor of the ocean. While the diet of most Sea Cucumbers consists of plankton and decaying organic matter found in the sea, others catch food that flows by with their tenticles. Many species have an esophagus and stomach, but in some the pharynx opens directly into the intenstine. The intestine is typically long and coiled, and loops through the body before terminating in a cloacol chamber, or directly as the anus.