cnidarians

Cnidarians are a diverse group of simple, aquatic animals that include jellyfish, corals, and sea anemones. They are characterized by their radial symmetry and possess specialized cells called cnidocytes, which contain stinging structures used for defense and capturing prey. Cnidarians typically have two body forms: the polyp, which is stationary, and the medusa, which is free-swimming. They are mainly found in marine environments and play crucial roles in ecosystems, such as forming coral reefs. Their simple body plan and unique traits make them an important subject of study in biology and marine science.