What functions does the echinoderm water-vascular system perform?

The water-vascular system is a characteristic hydraulic network in echinoderms that performs several vital functions. Its primary roles include:12

• Locomotion: The system is perhaps best known for facilitating movement. By regulating fluid pressure within the tube feet, echinoderms can extend, retract, and adhere to surfaces, allowing them to crawl or move across the seafloor.12
• Respiration: The system plays a significant role in gas exchange. Certain tube feet are specialized for high oxygen uptake, particularly in areas where water flow is unimpeded.12
• Feeding: The system supports various feeding strategies. For example, some species use modified tube feet as tentacles to capture plankton or manipulate food, while others use them to exert force on the shells of prey.2
• Sensory Perception: Tube feet are implicated in chemoreception and photoreception, helping the animal interact with its environment.2
• Other Functions: Depending on the species, the system may also be involved in burrow construction, mucus production, and general attachment to substrates.2