Which of the following has a water vascular system?

Which of the following has a water vascular system?

The water vascular system is found in the phylum Echinodermata.

What does a Pedicellariae do?

Pedicellariae are poorly understood but in some taxa, they are thought to keep the body surface clear of algae, encrusting organisms, and other debris in conjunction with the ciliated epidermis present in all echinoderms.

Do sea stars have an open Ambulacral groove?

Class Asteroidea – sea stars. Star shaped, with arms not sharply marked off from central disc; ambulacral grooves open, with tube feet on oral side; tube feet often with suckers; anus aboral; pedicellariae present.

Do crinoids have an open Ambulacral groove?

What is an ambulacrum and what is the difference between open and closed ambulacral grooves? A band of tube feet that extend from the mouth along the oral sides of each arm to its tip. When the tube feet are out then it is open. Most of the asteroids and crinoids are open.

Does Ophiuroidea have Ambulacral groove?

Ambulacral grooves are absent in the living forms of the class Ophiuroidea. These are replaced by ossicles in the animals belonging to the class Ophiuroidea. Ambulacral grooves extend from the mouth to the end of each ray or arm of the animal.

Do sea stars have ossicles?

Ossicles are small calcareous elements embedded in the dermis of the body wall of echinoderms. They form part of the endoskeleton and provide rigidity and protection. They are found in different forms and arrangements in sea urchins, starfish, brittle stars, sea cucumbers, and crinoids.

What class are sea stars in?

class Asteroidea

Do sea stars have segmentation?

Type of Body Plan: Their body has no segmentation but this doesn’t mean it doesn’t have repetition. For example, though a starfish is not segmented, it still contains the same organs in every appendage.

Can sea stars See?

Starfish, which are more scientifically known as sea stars, don’t have any visible body parts that look like eyes. A starfish has eyespots that cannot see much in the way of details but can detect light and dark. These eyespots are at the tip of each of the starfish’s arms.