Function of vascular water system in starfish?

Answer 1

Starfish move using a water vascular system. Water comes into the system via the madreporite. It is then circulated from the stone canal to the ring canal and into the radial canals. The radial canals carry water to the ampulla (reservoir) portion of tube feet. Each tube foot consists of an internal ampulla and an external podium, or "foot". When the ampulla is squeezed, it forces water into the podium, which expands to contact the substrate. In some circumstances the tube feet seem to work as levers, but when moving on vertical surfaces, they form a traction system. Although the podium resembles a suction cup in appearance, the gripping action is a function of adhesive chemicals rather than suction. Other chemicals and podial contraction allow for release off the substrate.

The tube feet latch on to surfaces and move in a wave, with one body section attaching to the surfaces as another releases.

Answer 2

Sieve Plate: Allows water to enter the starfish; keeps out pieces of debris.Ring Canal: Pumps water from the sieve plate to the radial canals.

Radial Canals: Allows water to flow to the tube feet.

Tube Feet: Help the starfish move, catch food, take in oxygen, and remove waste.

Ampullae: Bulb-like structure that connect to the tube feet and regulate water pressure.

Answer 3

just go to http://marine-francine.blogspot.com/2007/11/starfish.html hope this helps ;)