Question

............... are the locomotory organs of echinoderms.

• A. Parapodia
• B. Pseudopodia
• C. Setae
• D. Tube feet

Answer 1

The correct option is D Tube feet

Echinoderms are the organisms which are marine. They have radial form of symmetry. These organisms have tentacles which have been modified to form the tube like feet. They have five tube like feet. These organs are primarily used to move. There are certain species like the sea urchins which use the spines on their skin for locomotion. The tube feet have a tip shaped structure. There are suction or adhesive pads in the tube feet. This pads help the organism to create hydrostatic pressure or vacuum. The vacuum is created with the contraction of the muscles in the tube feet. This pressure helps the organism to move under the water.

Therefore, the correct answer is option D.