Echinodermata
Water Vascular System
Echinoderms are a phylum of marine animals that are found at every ocean depth. The phylum contains about 7000 living species and echinoderms are also the largest phylum that has no freshwater or land-based animals. Some characteristics are:
- An internal skeleton
- Have a water vascular system consisting of a network of radial canals, which extend through each of the five arms of the animal.
- Are radial symmetrical: the parts of the animal are arranged around a central axis
- An internal skeleton
- Have a water vascular system consisting of a network of radial canals, which extend through each of the five arms of the animal.
- Are radial symmetrical: the parts of the animal are arranged around a central axis