The Sea Anemone
Sea anemone are predatory water-dwellers, related to coral and jellyfish. They are rooted to surfaces by a hidden adhesive foot know as a base disk. Its mouth also acts as an anus, taking in food and expelling waste from the same opening. Tentacles surround its mouth to act as a defense mechanism as well as a means for capturing food. Its tentacles contain a small neurotoxin that is used for paralyzing its prey so it won't escape the anemone's grip.
The System
The mouth leads to an anemone's pharynx, or opening to its gastrovascular cavity. It spans about two to three feet until it reaches the cavity, which takes up the rest of the anemone's body. All members of the phylum Cnideria have a gastrovascular system, combining its cardiovascular and digestive system. The nutrients obtained in the gastrovascular cavity are then distributed to the rest of the body.