The Jellyfish's Cardiovascular system
Because jellyfish have no organs specialized in carrying out any respiratory, cardiovascular, and digestive systems, they have one gastrovascular system, which is a combination of all three in one. The anatomy of the jellyfish makes this a case in which needed nutrients and oxygen are absorbed through the epidermis, or outer layer, and then absorbed through the inner layer, the gastrodermis. From there it enters the gastrovascular cavity in which all nutrients and oxygen gather and diffuse to other parts of the body in which these necessities of life are needed. This gastrovascular system absorbs and distributes all things needed by the body just as the cardiovascular system should, but it does perform it in a very different manner. Because of the jellyfish having a carnivorous diet, as well as being able to filter feed, their mouth in which they eat other fish also performs as its anus. Because there is only one way to digest the food going in and out, jellyfish are unable to process food continuously.