Sea urchins are small , globe-shaped animals with
well developed spines. They are very closely
related to Sand dollars. They are found on the sea floor
Sea Urchins have a very simple, and undeveloped respiratory system. It is known as a water vascular system. Basically, it is a system that moves water throughout their body, and accounts for how they breathe, and gas exchange. In some circumstances, the Sea urchin will have gills, so this means that they will have a higher developed respiratory system then other Sea Urchins. Sea Urchins also have tube feet, which are organs the help them breathe as well. Sea Urchins are not very complex animals, and this body system, is not very complex at all, and it is very easy to understand.
Sea Urchins have a very simple, and undeveloped respiratory system. It is known as a water vascular system. Basically, it is a system that moves water throughout their body, and accounts for how they breathe, and gas exchange. In some circumstances, the Sea urchin will have gills, so this means that they will have a higher developed respiratory system then other Sea Urchins. Sea Urchins also have tube feet, which are organs the help them breathe as well. Sea Urchins are not very complex animals, and this body system, is not very complex at all, and it is very easy to understand.