What are the five main features of cnidarians?

Cnidarians are characterized by five main features: they possess a radial symmetry, allowing them to interact with their environment from all directions; they have specialized cells called cnidocytes, which contain stinging structures used for capturing prey and defense; they exhibit two main body forms—polyp and medusa; they have a simple body plan with a gelatinous mesoglea layer between the epidermis and gastrodermis; and they possess a central gastrovascular cavity for digestion and nutrient distribution. These features enable cnidarians to thrive in diverse aquatic environments.