EVERYDAY SCIENCE

Detailed explanation-1: -Answer and Explanation: The option that is NOT correct is: (a) The adult body is bilaterally symmetrical. The adult cnidarians are not bilaterally symmetrical.

Detailed explanation-2: -Mostly marine animals, the cnidarians include the corals, hydras, jellyfish, Portuguese men-of-war, sea anemones, sea pens, sea whips, and sea fans.

Detailed explanation-3: -There are two basic cnidarian body shapes: a polyp form, which is attached to a surface; and an upside-down free-floating form called a medusa. Some cnidarians change form at different phases of their life cycle, while others remain in one form for their entire life.

Detailed explanation-4: -Because the tentacles of corals, jellyfish, and sea anemones have this radial structure, they can sting and capture food coming from any direction. Many cnidarians take two main structural forms during their life cycles, a polyp form and a medusa form.