Muscular System of Sea Stars
A sea star does not have much of a muscular system. It contains long and circular muscles in both its epidermis and dermis. A sea star's foot also contains muscles. It works by becoming shorter at times to send sea water with minerals up through its body. Sea stars move by a way of something called the water vascular system, so it does not need any muscles to move. This is why a sea star has such a simple muscular system.