Cnidaria
Just as animals in the Porifera phylum do, animals in the Cnidaria Phylum carry out circulation throughout the body through the process of diffusion. Cnidaria animals' circulatory system moves blood to a site where it can be oxygenated. Wastes can also be disposed at these sites. Circulation then brings newly oxygenated blood to the tissues throughout the body. Oxygen and other chemicals diffuse out of the blood cells and into the fluid surrounding the cells of the body's tissues. Waste products diffuse into the blood cells and are carried away. Blood circulates by the means of organs. Some of these organs include the liver and kidneys. This process repeats in a continuous loop.
Sea Anemones and Coral do not have a true circulatory system. Their stomachs serve as their circulatory system. The stomach of these two animals is a gastrovascular system. A gastrovascular system is the digestive-excretory system without canals. They also are given better circulation through the many species of fish that live symbiotically with the coral and sea anemone. The clownfish, for example, is protected and is provided with a home. Concurrently, as the clownfish swims, it provides a current. This current allows for more circulation in and out of the sea anemone.
A circulatory system's chief duty is to transfer oxygen and nutrients to all the cells of the body, as well as to remove waste. A circulatory system is just unnecessary for Cnidarian animals, as there are no cells that need oxygen and nutrients delivered to them.
Sea Anemones and Coral do not have a true circulatory system. Their stomachs serve as their circulatory system. The stomach of these two animals is a gastrovascular system. A gastrovascular system is the digestive-excretory system without canals. They also are given better circulation through the many species of fish that live symbiotically with the coral and sea anemone. The clownfish, for example, is protected and is provided with a home. Concurrently, as the clownfish swims, it provides a current. This current allows for more circulation in and out of the sea anemone.
A circulatory system's chief duty is to transfer oxygen and nutrients to all the cells of the body, as well as to remove waste. A circulatory system is just unnecessary for Cnidarian animals, as there are no cells that need oxygen and nutrients delivered to them.