Question

Radial symmetry of echinoderms is

• A. Primary
• B. Secondary
• C. Biradial
• D. Triradial

Answer 1

Answer: (B)

Secondary

A) Primary symmetry is bilateral in case of echinoderms.

B) Echinoderm larva are bilaterally symmetrical and develop into adults that are radially symmetrical. Therefore, echinoderms have secondary radial symmetry.

C) Echinoderms are not biradial, they are pentaradial.

D) Echinoderms are not triradial, they are pentaradial.

So the correct answer is 'Secondary'.