Do starfish have an open or closed circulatory system?

Starfish have an open circulatory system. In an open circulatory system, blood is not enclosed within vessels, but instead flows freely through the body cavity, also called the hemocoel. The blood is pumped by the heart into the hemocoel, where it bathes the organs and tissues, delivering nutrients and oxygen and removing waste products. Then, the blood is collected and returned to the heart through a system of channels and sinuses.