Describe the sexual life cycle of a Cnidarians??
Cnidarians have two body forms: the polyp and the medusa. Free-swimming medusa release their gametes (eggs or sperm) into the surrounding water. Eggs are fertilized by sperm and develop into the larval stage, during which they are still free-swimming and are called planulae. Once the larva reaches a certain stage of development it will attach to the substrate and become a polyp. An individual with the polyp form is usually anchored to the substrate with the mouth facing upwards. Over time the polyp begins to segment itself, and each segment eventually becomes a separate organism. When the segments break apart, the now free-swimming medusae become independent individuals in a process called strobilation. These released individuals are called ephyrae and that mature into adults repeating the reproduction cycle.