Jellyfish have specialized cells that sting predators in order to eat them. They also have specialized groups of tissues that form organs, unlike the sponges who have no specialized tissues. Jellyfish have digestive organs as well as reproductive organs. They also have two sensory organs; one of which is used to sense light, and another that they use to balance themselves. Jellyfish have a hydro-skeleton as well, but sponges don’t have a skeletal system at all.