Question

Body symmetry in Echinodermata is:

• A. radial
• B. bilateral
• C. asymmetric
• D. all

Answer 1

The correct option is A

radial

The correct option is: A

Explanation of the correct option:

Symmetry refers to the correspondence of body parts, in size, shape, and relative position, on opposite sides of a dividing line or distributed around a central point or axis.

There are four types of symmetry that occur among animals:

1. Spherical: If the organism is cut through its center, the resulting parts look the same. E.g.Some members of the single-celled protozoan group Radiolaria
2. Radial: Radial symmetry is a type of body symmetry, where any plane passing through the center divides the body into two equal halves. E.g. Echinoderms, Coelenterates, etc.
3. Bilateral: When the body of an organism can be divided into two halves, it is referred to as bilateral symmetry. E.g. Annelids, Arthropods, Molluscs, Chordates, etc.

The organisms belonging to the phylum Echinodermata are exclusively marine. Adult echinoderms have radial symmetry while their larva has bilateral symmetry.

Final answer: Body symmetry in Echinodermata is radial.