Jellyfish are relatively simple organisms. They are made up of approximately 95 percent water, and have no heart or blood. Aside from not needing to eat or move consciously, they can absorb oxygen through their thin bodies and distribute it effortlessly to whichever tissues require a new supply of the vital element. Jellyfish are unique organisms in this way as they do not specifically have a traditional circulatory system. This direct diffusion of the nutrients by the outer layer of the Jellyfish also allows for the second inner layer of the Jellyfish to receive all the nutrients, materials, and oxygen necessary for it's survival.