Question

Echinoderms

• A. are radially symmetrical
• B. have an internal skeleton called as endoskeleton
• C. are exclusively marine
• D. all of the above

Answer 1

The correct option is D all of the above

All the statements are true with respect to echinoderms.
The larvae of echinoderms are bilaterally symmetrical and adults are radially symmetrical. Organisms exhibiting bilateral symmetry can be cut into two identical halves in only one plane, the median sagittal plane.
Organisms exhibiting radial symmetry can be cut into two identical halves in any plane passing through the centre.
The echinoderms have endoskeleton made of calcareous ossicles. All echinoderms are exclusively marine.