Which system is utilized by echinoderms like starfish for movement and feeding?

The water-vascular system is a unique network of fluid-filled canals and tubes found in echinoderms, such as starfish. This system plays a crucial role in both locomotion and feeding. It operates by using hydraulic pressure to extend and retract tube feet, which allows these animals to move across surfaces and manipulate prey.

Starfish utilize their tube feet to cling to rocks and substrates, aiding in movement. Additionally, the coordinated action of these tube feet helps them to pry open bivalves, which are a significant part of their diet. The water-vascular system functions as a means of transportation and feeding, making it essential for the survival of echinoderms.

In contrast, the digestive system is primarily concerned with processing food rather than movement, the excretory system is involved in waste elimination, and the respiratory system handles gas exchange. Therefore, the water-vascular system is the system specifically adapted for the distinctive methods of movement and feeding among echinoderms.