Ans: Jellyfish are made up of a smooth bag-like body, with tentacles armed with tiny sting cells. They usually sting their prey before eating it. Studies indicate that they have a dual purple system which helps them to travel great distances with less effort. Hence they are called energy-efficient.The jellyfish can quickly digest their food, which consists of fish, shrimp, crab and tiny plants. The jellyfish have the ability to clone themselves. They do not have bones, heart or brain, they comprise 95 % of water. Jellyfish consists of structural proteins, nerve cells, and muscle cells along with the water. The jellyfish moves in water by squirting a jet of water from its mouth, they seem to propel forward.