Sea Star
Sea stars are characterized by having 5 or more arms attached radially to a central point. They are usually covered in spines to help defend against predators. The sea star has an endoskeleton made of calcerous plates, covered by thin skin. The undersides of their arms bear tube feet used in locomotion, feeding, and gas exchange. Through hydraulics and muscular action these tube feet become little suction cups. They can just as well turn off the suction. When prey ventures close, a sea star will grasp it using their tube feet. Then the sea star turns their stomach inside out and ejects it through their mouth into the prey. They secrete juices that start to digest their soft bodied prey such as molluscs within their own shell. Gametes are released into the seawater by male and female individuals in sexual reproduction. Sea stars are also capable of regeneration. If an arm is lost, they are capable of growing a new one. Some sea stars can even grow an entire body from a single arm.
