Jellyfish is a coelenterate, but also an invertebrate, their species are very many, in all parts of the world are distributed. Their body structure is very different from that of humans and most animals, and there are some organs that do not exist in the body structure of jellyfish. For example, the heart, jellyfish's body is not the heart, which is different from most animals; In addition, there are no brains, lungs and so on in their bodies.
In fact, the body structure of jellyfish is mainly water. Although humans are also mainly made up of water, water accounts for significantly more of jellyfish's body than humans and other animals, because water accounts for 95% of their body. Because their bodies are mainly water, jellyfish are generally transparent or translucent in appearance, looking like transparent jelly or colloid. Also, it makes their bodies very soft.
As mentioned above, as a coelenterate jellyfish, the body structure is very special, there are some more important structures in their bodies do not exist, such as the heart, brain and so on. In addition, there is another structure that does not exist in their bodies, such as bone. Jellyfish have no bones, so they can keep their bodies in a very soft state. Generally speaking, their bodies are umbrella-shaped, but their seemingly very large bodies can pass through a very small hole, precisely because they have no bones.
